645455631534 has 32 divisors (see below), whose sum is σ = 1476953846016. Its totient is φ = 184212558720.

The previous prime is 645455631523. The next prime is 645455631539. The reversal of 645455631534 is 435136554546.

It is a happy number.

It is a super-2 number, since 2×645455631534² (a number of 24 digits) contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645455631539) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 8433787 + ... + 8509974.

It is an arithmetic number, because the mean of its divisors is an integer number (46154807688).

Almost surely, 2^645455631534 is an apocalyptic number.

645455631534 is an abundant number, since it is smaller than the sum of its proper divisors (831498214482).

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

645455631534 is a wasteful number, since it uses less digits than its factorization.

645455631534 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16944680.

The product of its digits is 12960000, while the sum is 51.

The spelling of 645455631534 in words is "six hundred forty-five billion, four hundred fifty-five million, six hundred thirty-one thousand, five hundred thirty-four".