21372446 has 4 divisors (see below), whose sum is σ = 32058672. Its totient is φ = 10686222.

The previous prime is 21372437. The next prime is 21372469. The reversal of 21372446 is 64427312.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5343110 + ... + 5343113.

It is an arithmetic number, because the mean of its divisors is an integer number (8014668).

Almost surely, 2^21372446 is an apocalyptic number.

21372446 is a deficient number, since it is larger than the sum of its proper divisors (10686226).

21372446 is a wasteful number, since it uses less digits than its factorization.

21372446 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10686225.

The product of its digits is 8064, while the sum is 29.

The square root of 21372446 is about 4623.0342849691. The cubic root of 21372446 is about 277.5139013137.

Adding to 21372446 its reverse (64427312), we get a palindrome (85799758).

The spelling of 21372446 in words is "twenty-one million, three hundred seventy-two thousand, four hundred forty-six".