646507028 has 6 divisors (see below), whose sum is σ = 1131387306. Its totient is φ = 323253512.

The previous prime is 646507027. The next prime is 646507051. The reversal of 646507028 is 820705646.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 573027844 + 73479184 = 23938^2 + 8572^2 .

It is a junction number, because it is equal to n+sod(n) for n = 646506982 and 646507000.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (646507027) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80813375 + ... + 80813382.

It is an arithmetic number, because the mean of its divisors is an integer number (188564551).

Almost surely, 2^646507028 is an apocalyptic number.

It is an amenable number.

646507028 is a deficient number, since it is larger than the sum of its proper divisors (484880278).

646507028 is a wasteful number, since it uses less digits than its factorization.

646507028 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 161626761 (or 161626759 counting only the distinct ones).

The product of its (nonzero) digits is 80640, while the sum is 38.

The square root of 646507028 is about 25426.5024728137. The cubic root of 646507028 is about 864.6846514406.

The spelling of 646507028 in words is "six hundred forty-six million, five hundred seven thousand, twenty-eight".