672000021 has 48 divisors (see below), whose sum is σ = 1281391488. Its totient is φ = 328550400.

The previous prime is 672000013. The next prime is 672000023. The reversal of 672000021 is 120000276.

It is a happy number.

It is not a de Polignac number, because 672000021 - 2³ = 672000013 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 671999958 and 672000003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (672000023) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 16740 + ... + 40301.

It is an arithmetic number, because the mean of its divisors is an integer number (26695656).

Almost surely, 2^672000021 is an apocalyptic number.

It is an amenable number.

672000021 is a deficient number, since it is larger than the sum of its proper divisors (609391467).

672000021 is a wasteful number, since it uses less digits than its factorization.

672000021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 57082 (or 57079 counting only the distinct ones).

The product of its (nonzero) digits is 168, while the sum is 18.

The square root of 672000021 is about 25922.9631986777. The cubic root of 672000021 is about 875.9038371016.

Adding to 672000021 its reverse (120000276), we get a palindrome (792000297).

It can be divided in two parts, 6 and 72000021, that added together give a palindrome (72000027).

The spelling of 672000021 in words is "six hundred seventy-two million, twenty-one", and thus it is an aban number.