21930580 has 48 divisors (see below), whose sum is σ = 52899840. Its totient is φ = 7481088.

The previous prime is 21930577. The next prime is 21930589. The reversal of 21930580 is 8503912.

It is a super-3 number, since 3×21930580³ (a number of 23 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (28).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21930589) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 53416 + ... + 53824.

It is an arithmetic number, because the mean of its divisors is an integer number (1102080).

Almost surely, 2^21930580 is an apocalyptic number.

21930580 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21930580 is an abundant number, since it is smaller than the sum of its proper divisors (30969260).

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

21930580 is a wasteful number, since it uses less digits than its factorization.

21930580 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 808 (or 806 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 28.

The square root of 21930580 is about 4683.0097159839. The cubic root of 21930580 is about 279.9088989339.

The spelling of 21930580 in words is "twenty-one million, nine hundred thirty thousand, five hundred eighty".