630521428 has 6 divisors (see below), whose sum is σ = 1103412506. Its totient is φ = 315260712.

The previous prime is 630521407. The next prime is 630521473. The reversal of 630521428 is 824125036.

It can be written as a sum of positive squares in only one way, i.e., 513838224 + 116683204 = 22668^2 + 10802^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 630521428.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 78815175 + ... + 78815182.

Almost surely, 2^630521428 is an apocalyptic number.

It is an amenable number.

630521428 is a deficient number, since it is larger than the sum of its proper divisors (472891078).

630521428 is a wasteful number, since it uses less digits than its factorization.

630521428 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 157630361 (or 157630359 counting only the distinct ones).

The product of its (nonzero) digits is 11520, while the sum is 31.

The square root of 630521428 is about 25110.1857420450. The cubic root of 630521428 is about 857.4983311343.

The spelling of 630521428 in words is "six hundred thirty million, five hundred twenty-one thousand, four hundred twenty-eight".