21472623 has 6 divisors (see below), whose sum is σ = 31016024. Its totient is φ = 14315076.

The previous prime is 21472621. The next prime is 21472631. The reversal of 21472623 is 32627412.

It is not a de Polignac number, because 21472623 - 2¹ = 21472621 is a prime.

It is a super-2 number, since 2×21472623² = 922147077000258, which contains 22 as substring.

It is a Duffinian number.

It is a plaindrome in base 11.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21472621) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1192915 + ... + 1192932.

Almost surely, 2^21472623 is an apocalyptic number.

21472623 is a deficient number, since it is larger than the sum of its proper divisors (9543401).

21472623 is a wasteful number, since it uses less digits than its factorization.

21472623 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2385853 (or 2385850 counting only the distinct ones).

The product of its digits is 4032, while the sum is 27.

The square root of 21472623 is about 4633.8561695417. The cubic root of 21472623 is about 277.9468136611.

The spelling of 21472623 in words is "twenty-one million, four hundred seventy-two thousand, six hundred twenty-three".