21372080 has 40 divisors (see below), whose sum is σ = 49883712. Its totient is φ = 8515584.

The previous prime is 21372079. The next prime is 21372089. The reversal of 21372080 is 8027312.

It is a tau number, because it is divible by the number of its divisors (40).

It is not an unprimeable number, because it can be changed into a prime (21372089) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 36752 + ... + 37328.

Almost surely, 2^21372080 is an apocalyptic number.

21372080 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21372080 is an abundant number, since it is smaller than the sum of its proper divisors (28511632).

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

21372080 is a wasteful number, since it uses less digits than its factorization.

21372080 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1053 (or 1047 counting only the distinct ones).

The product of its (nonzero) digits is 672, while the sum is 23.

The square root of 21372080 is about 4622.9947004080. The cubic root of 21372080 is about 277.5123171764.

Adding to 21372080 its reverse (8027312), we get a palindrome (29399392).

The spelling of 21372080 in words is "twenty-one million, three hundred seventy-two thousand, eighty".