21473242 has 16 divisors (see below), whose sum is σ = 37317312. Its totient is φ = 9076320.

The previous prime is 21473239. The next prime is 21473267. The reversal of 21473242 is 24237412.

It is a happy number.

It is a super-2 number, since 2×21473242² = 922200243981128, which contains 22 as substring.

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, 9484 + ... + 11527.

It is an arithmetic number, because the mean of its divisors is an integer number (2332332).

Almost surely, 2^21473242 is an apocalyptic number.

21473242 is a deficient number, since it is larger than the sum of its proper divisors (15844070).

21473242 is a wasteful number, since it uses less digits than its factorization.

21473242 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21093.

The product of its digits is 2688, while the sum is 25.

The square root of 21473242 is about 4633.9229600847. The cubic root of 21473242 is about 277.9494844638.

The spelling of 21473242 in words is "twenty-one million, four hundred seventy-three thousand, two hundred forty-two".