1261016544 has 48 divisors (see below), whose sum is σ = 3314645712. Its totient is φ = 419770368.

The previous prime is 1261016539. The next prime is 1261016639. The reversal of 1261016544 is 4456101621.

It is a tau number, because it is divible by the number of its divisors (48).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 65712 + ... + 82704.

It is an arithmetic number, because the mean of its divisors is an integer number (69055119).

Almost surely, 2^1261016544 is an apocalyptic number.

It is an amenable number.

1261016544 is an abundant number, since it is smaller than the sum of its proper divisors (2053629168).

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

1261016544 is a wasteful number, since it uses less digits than its factorization.

1261016544 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17779 (or 17771 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 30.

The square root of 1261016544 is about 35510.7947531451. The cubic root of 1261016544 is about 1080.3726834519.

The spelling of 1261016544 in words is "one billion, two hundred sixty-one million, sixteen thousand, five hundred forty-four".