261533524721145 has 32 divisors (see below), whose sum is σ = 428187006618624. Its totient is φ = 136240119422400.

The previous prime is 261533524721113. The next prime is 261533524721239. The reversal of 261533524721145 is 541127425335162.

It is not a de Polignac number, because 261533524721145 - 2⁵ = 261533524721113 is a prime.

It is a super-2 number, since 2×261533524721145² (a number of 30 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 171268450 + ... + 172788740.

It is an arithmetic number, because the mean of its divisors is an integer number (13380843956832).

Almost surely, 2^{261533524721145} is an apocalyptic number.

It is an amenable number.

261533524721145 is a deficient number, since it is larger than the sum of its proper divisors (166653481897479).

261533524721145 is a wasteful number, since it uses less digits than its factorization.

261533524721145 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1787053.

The product of its digits is 6048000, while the sum is 51.

The spelling of 261533524721145 in words is "two hundred sixty-one trillion, five hundred thirty-three billion, five hundred twenty-four million, seven hundred twenty-one thousand, one hundred forty-five".