261430431571632 has 160 divisors (see below), whose sum is σ = 692500357140480. Its totient is φ = 84936203735040.

The previous prime is 261430431571613. The next prime is 261430431571637. The reversal of 261430431571632 is 236175134034162.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is not an unprimeable number, because it can be changed into a prime (261430431571637) 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, 9496532844 + ... + 9496560372.

It is an arithmetic number, because the mean of its divisors is an integer number (4328127232128).

Almost surely, 2^{261430431571632} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 261430431571632, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (346250178570240).

261430431571632 is an abundant number, since it is smaller than the sum of its proper divisors (431069925568848).

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

261430431571632 is a wasteful number, since it uses less digits than its factorization.

261430431571632 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32051 (or 32045 counting only the distinct ones).

The product of its (nonzero) digits is 2177280, while the sum is 48.

The spelling of 261430431571632 in words is "two hundred sixty-one trillion, four hundred thirty billion, four hundred thirty-one million, five hundred seventy-one thousand, six hundred thirty-two".