21719072 has 12 divisors (see below), whose sum is σ = 42759486. Its totient is φ = 10859520.

The previous prime is 21719069. The next prime is 21719099. The reversal of 21719072 is 27091712.

It can be written as a sum of positive squares in only one way, i.e., 21492496 + 226576 = 4636^2 + 476^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 339329 + ... + 339392.

Almost surely, 2^21719072 is an apocalyptic number.

It is an amenable number.

21719072 is a deficient number, since it is larger than the sum of its proper divisors (21040414).

21719072 is an equidigital number, since it uses as much as digits as its factorization.

21719072 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 678731 (or 678723 counting only the distinct ones).

The product of its (nonzero) digits is 1764, while the sum is 29.

The square root of 21719072 is about 4660.3725172994. The cubic root of 21719072 is about 279.0061363056.

The spelling of 21719072 in words is "twenty-one million, seven hundred nineteen thousand, seventy-two".