672745521 has 24 divisors (see below), whose sum is σ = 1081942464. Its totient is φ = 364188960.

The previous prime is 672745501. The next prime is 672745523. The reversal of 672745521 is 125547276.

It is not a de Polignac number, because 672745521 - 2⁶ = 672745457 is a prime.

It is a super-2 number, since 2×672745521² = 905173072051122882, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 672745521.

It is not an unprimeable number, because it can be changed into a prime (672745523) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 36790 + ... + 51951.

It is an arithmetic number, because the mean of its divisors is an integer number (45080936).

Almost surely, 2^672745521 is an apocalyptic number.

It is an amenable number.

672745521 is a deficient number, since it is larger than the sum of its proper divisors (409196943).

672745521 is a wasteful number, since it uses less digits than its factorization.

672745521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 88789 (or 88770 counting only the distinct ones).

The product of its digits is 117600, while the sum is 39.

The square root of 672745521 is about 25937.3383561228. The cubic root of 672745521 is about 876.2276193288.

The spelling of 672745521 in words is "six hundred seventy-two million, seven hundred forty-five thousand, five hundred twenty-one".