21727492 has 6 divisors (see below), whose sum is σ = 38023118. Its totient is φ = 10863744.

The previous prime is 21727487. The next prime is 21727493. The reversal of 21727492 is 29472712.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 12278016 + 9449476 = 3504^2 + 3074^2 .

It is a super-2 number, since 2×21727492² = 944167817220128, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21727493) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2715933 + ... + 2715940.

Almost surely, 2^21727492 is an apocalyptic number.

It is an amenable number.

21727492 is a deficient number, since it is larger than the sum of its proper divisors (16295626).

21727492 is a wasteful number, since it uses less digits than its factorization.

21727492 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5431877 (or 5431875 counting only the distinct ones).

The product of its digits is 14112, while the sum is 34.

The square root of 21727492 is about 4661.2757910255. The cubic root of 21727492 is about 279.0421864669.

The spelling of 21727492 in words is "twenty-one million, seven hundred twenty-seven thousand, four hundred ninety-two".