261564213601131 has 32 divisors (see below), whose sum is σ = 402530458337280. Its totient is φ = 147982233684384.

The previous prime is 261564213601123. The next prime is 261564213601181. The reversal of 261564213601131 is 131106312465162.

261564213601131 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 261564213601131 - 2³ = 261564213601123 is a prime.

It is a super-2 number, since 2×261564213601131² (a number of 30 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (261564213601181) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2999535 + ... + 23067848.

It is an arithmetic number, because the mean of its divisors is an integer number (12579076823040).

Almost surely, 2^{261564213601131} is an apocalyptic number.

261564213601131 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

261564213601131 is a deficient number, since it is larger than the sum of its proper divisors (140966244736149).

261564213601131 is a wasteful number, since it uses less digits than its factorization.

261564213601131 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26072135.

The product of its (nonzero) digits is 155520, while the sum is 42.

The spelling of 261564213601131 in words is "two hundred sixty-one trillion, five hundred sixty-four billion, two hundred thirteen million, six hundred one thousand, one hundred thirty-one".