21980630 has 32 divisors (see below), whose sum is σ = 45679680. Its totient is φ = 7459200.

The previous prime is 21980593. The next prime is 21980653. The reversal of 21980630 is 3608912.

It is a Smith number, since the sum of its digits (29) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a junction number, because it is equal to n+sod(n) for n = 21980593 and 21980602.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5516 + ... + 8624.

It is an arithmetic number, because the mean of its divisors is an integer number (1427490).

Almost surely, 2^21980630 is an apocalyptic number.

21980630 is an abundant number, since it is smaller than the sum of its proper divisors (23699050).

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

21980630 is a wasteful number, since it uses less digits than its factorization.

21980630 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3224.

The product of its (nonzero) digits is 2592, while the sum is 29.

The square root of 21980630 is about 4688.3504561839. The cubic root of 21980630 is about 280.1216733100.

The spelling of 21980630 in words is "twenty-one million, nine hundred eighty thousand, six hundred thirty".