1261463061511 has 4 divisors (see below), whose sum is σ = 1304961787800. Its totient is φ = 1217964335224.

The previous prime is 1261463061497. The next prime is 1261463061553. The reversal of 1261463061511 is 1151603641621.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1261463061511 - 2²³ = 1261454672903 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1261463061011) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 21749363101 + ... + 21749363158.

It is an arithmetic number, because the mean of its divisors is an integer number (326240446950).

Almost surely, 2^{1261463061511} is an apocalyptic number.

1261463061511 is a deficient number, since it is larger than the sum of its proper divisors (43498726289).

1261463061511 is an equidigital number, since it uses as much as digits as its factorization.

1261463061511 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43498726288.

The product of its (nonzero) digits is 25920, while the sum is 37.

The spelling of 1261463061511 in words is "one trillion, two hundred sixty-one billion, four hundred sixty-three million, sixty-one thousand, five hundred eleven".