261306156064 has 48 divisors (see below), whose sum is σ = 519898974336. Its totient is φ = 129270112000.

The previous prime is 261306156053. The next prime is 261306156073. The reversal of 261306156064 is 460651603162.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4778799 + ... + 4833169.

It is an arithmetic number, because the mean of its divisors is an integer number (10831228632).

Almost surely, 2^261306156064 is an apocalyptic number.

It is an amenable number.

261306156064 is a deficient number, since it is larger than the sum of its proper divisors (258592818272).

261306156064 is a wasteful number, since it uses less digits than its factorization.

261306156064 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55969 (or 55961 counting only the distinct ones).

The product of its (nonzero) digits is 155520, while the sum is 40.

The spelling of 261306156064 in words is "two hundred sixty-one billion, three hundred six million, one hundred fifty-six thousand, sixty-four".