634961405391 has 8 divisors (see below), whose sum is σ = 846619674240. Its totient is φ = 423305370072.

The previous prime is 634961405389. The next prime is 634961405413. The reversal of 634961405391 is 193504169436.

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

It is not a de Polignac number, because 634961405391 - 2¹ = 634961405389 is a prime.

It is a super-2 number, since 2×634961405391² (a number of 24 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (634961405371) 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, 288406 + ... + 1163228.

It is an arithmetic number, because the mean of its divisors is an integer number (105827459280).

Almost surely, 2^634961405391 is an apocalyptic number.

634961405391 is a deficient number, since it is larger than the sum of its proper divisors (211658268849).

634961405391 is a wasteful number, since it uses less digits than its factorization.

634961405391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1116765.

The product of its (nonzero) digits is 2099520, while the sum is 51.

The spelling of 634961405391 in words is "six hundred thirty-four billion, nine hundred sixty-one million, four hundred five thousand, three hundred ninety-one".