1261133492004 has 135 divisors (see below), whose sum is σ = 3339074851651. Its totient is φ = 415061539200.

The previous prime is 1261133491967. The next prime is 1261133492027. The reversal of 1261133492004 is 4002943311621.

The square root of 1261133492004 is 1123002.

It is a perfect power (a square), and thus also a powerful number.

1261133492004 is a `hidden beast` number, since 1 + 2 + 611 + 3 + 34 + 9 + 2 + 0 + 0 + 4 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 6823090404 + 1254310401600 = 82602^2 + 1119960^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1261133492004.

It is an unprimeable number.

It is a polite number, since it can be written in 44 ways as a sum of consecutive naturals, for example, 1799048854 + ... + 1799049554.

Almost surely, 2^{1261133492004} is an apocalyptic number.

1261133492004 is the 1123002-nd square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1261133492004

1261133492004 is an abundant number, since it is smaller than the sum of its proper divisors (2077941359647).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1261133492004 is an frugal number, since it uses more digits than its factorization.

1261133492004 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1596 (or 795 counting only the distinct ones).

The product of its (nonzero) digits is 31104, while the sum is 36.

Multiplying 1261133492004 by its sum of digits (36), we get a square (45400805712144 = 6738012²).

1261133492004 divided by its sum of digits (36) gives a square (35031485889 = 187167²).

The spelling of 1261133492004 in words is "one trillion, two hundred sixty-one billion, one hundred thirty-three million, four hundred ninety-two thousand, four".