21132370 has 32 divisors (see below), whose sum is σ = 45763200. Its totient is φ = 6863616.

The previous prime is 21132341. The next prime is 21132383. The reversal of 21132370 is 7323112.

It is a Harshad number since it is a multiple of its sum of digits (19).

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, 6615 + ... + 9274.

It is an arithmetic number, because the mean of its divisors is an integer number (1430100).

Almost surely, 2^21132370 is an apocalyptic number.

21132370 is an abundant number, since it is smaller than the sum of its proper divisors (24630830).

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

21132370 is a wasteful number, since it uses less digits than its factorization.

21132370 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15922.

The product of its (nonzero) digits is 252, while the sum is 19.

The square root of 21132370 is about 4596.9957581012. The cubic root of 21132370 is about 276.4708845362.

Adding to 21132370 its reverse (7323112), we get a palindrome (28455482).

The spelling of 21132370 in words is "twenty-one million, one hundred thirty-two thousand, three hundred seventy".