261553772137110 has 128 divisors (see below), whose sum is σ = 634870133452800. Its totient is φ = 68958943612416.

The previous prime is 261553772137081. The next prime is 261553772137153. The reversal of 261553772137110 is 11731277355162.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 2187777616 + ... + 2187897164.

It is an arithmetic number, because the mean of its divisors is an integer number (4959922917600).

Almost surely, 2^{261553772137110} is an apocalyptic number.

261553772137110 is an abundant number, since it is smaller than the sum of its proper divisors (373316361315690).

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

261553772137110 is a wasteful number, since it uses less digits than its factorization.

261553772137110 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 122022.

The product of its (nonzero) digits is 1852200, while the sum is 51.

The spelling of 261553772137110 in words is "two hundred sixty-one trillion, five hundred fifty-three billion, seven hundred seventy-two million, one hundred thirty-seven thousand, one hundred ten".