261449248728 has 32 divisors (see below), whose sum is σ = 653866536960. Its totient is φ = 87117294240.

The previous prime is 261449248727. The next prime is 261449248757. The reversal of 261449248728 is 827842944162.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261449248721) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1962628 + ... + 2091603.

It is an arithmetic number, because the mean of its divisors is an integer number (20433329280).

Almost surely, 2^261449248728 is an apocalyptic number.

It is an amenable number.

261449248728 is an abundant number, since it is smaller than the sum of its proper divisors (392417288232).

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

261449248728 is a wasteful number, since it uses less digits than its factorization.

261449248728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4056927 (or 4056923 counting only the distinct ones).

The product of its digits is 12386304, while the sum is 57.

The spelling of 261449248728 in words is "two hundred sixty-one billion, four hundred forty-nine million, two hundred forty-eight thousand, seven hundred twenty-eight".