261533537251051 has 12 divisors (see below), whose sum is σ = 283203008474880. Its totient is φ = 241412187650400.

The previous prime is 261533537251037. The next prime is 261533537251057. The reversal of 261533537251051 is 150152735335162.

It is not a de Polignac number, because 261533537251051 - 2¹⁷ = 261533537119979 is a prime.

It is a super-2 number, since 2×261533537251051² (a number of 30 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 261533537250986 and 261533537251004.

It is not an unprimeable number, because it can be changed into a prime (261533537251057) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1277905 + ... + 22906333.

It is an arithmetic number, because the mean of its divisors is an integer number (23600250706240).

Almost surely, 2^{261533537251051} is an apocalyptic number.

261533537251051 is a deficient number, since it is larger than the sum of its proper divisors (21669471223829).

261533537251051 is a wasteful number, since it uses less digits than its factorization.

261533537251051 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21700006 (or 21699993 counting only the distinct ones).

The product of its (nonzero) digits is 2835000, while the sum is 49.

The spelling of 261533537251051 in words is "two hundred sixty-one trillion, five hundred thirty-three billion, five hundred thirty-seven million, two hundred fifty-one thousand, fifty-one".