646344154531 has 4 divisors (see below), whose sum is σ = 658539327312. Its totient is φ = 634148981752.

The previous prime is 646344154529. The next prime is 646344154537. The reversal of 646344154531 is 135451443646.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 646344154531 - 2¹ = 646344154529 is a prime.

It is a super-2 number, since 2×646344154531² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (646344154537) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6097586311 + ... + 6097586416.

It is an arithmetic number, because the mean of its divisors is an integer number (164634831828).

Almost surely, 2^646344154531 is an apocalyptic number.

646344154531 is a deficient number, since it is larger than the sum of its proper divisors (12195172781).

646344154531 is a wasteful number, since it uses less digits than its factorization.

646344154531 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12195172780.

The product of its digits is 2073600, while the sum is 46.

The spelling of 646344154531 in words is "six hundred forty-six billion, three hundred forty-four million, one hundred fifty-four thousand, five hundred thirty-one".