261534253056631 has 8 divisors (see below), whose sum is σ = 267115471717824. Its totient is φ = 255953728565760.

The previous prime is 261534253056623. The next prime is 261534253056641. The reversal of 261534253056631 is 136650352435162.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 261534253056631 - 2³ = 261534253056623 is a prime.

It is a super-2 number, since 2×261534253056631² (a number of 30 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261534253056611) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 172780990 + ... + 174288091.

It is an arithmetic number, because the mean of its divisors is an integer number (33389433964728).

Almost surely, 2^{261534253056631} is an apocalyptic number.

261534253056631 is a deficient number, since it is larger than the sum of its proper divisors (5581218661193).

261534253056631 is a wasteful number, since it uses less digits than its factorization.

261534253056631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 347085161.

The product of its (nonzero) digits is 11664000, while the sum is 52.

The spelling of 261534253056631 in words is "two hundred sixty-one trillion, five hundred thirty-four billion, two hundred fifty-three million, fifty-six thousand, six hundred thirty-one".