21727642 has 16 divisors (see below), whose sum is σ = 33482592. Its totient is φ = 10568880.

The previous prime is 21727639. The next prime is 21727661. The reversal of 21727642 is 24672712.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 39892 + ... + 40432.

It is an arithmetic number, because the mean of its divisors is an integer number (2092662).

Almost surely, 2^21727642 is an apocalyptic number.

21727642 is a deficient number, since it is larger than the sum of its proper divisors (11754950).

21727642 is a wasteful number, since it uses less digits than its factorization.

21727642 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1053.

The product of its digits is 9408, while the sum is 31.

The square root of 21727642 is about 4661.2918810132. The cubic root of 21727642 is about 279.0428286063.

The spelling of 21727642 in words is "twenty-one million, seven hundred twenty-seven thousand, six hundred forty-two".