21471842 has 16 divisors (see below), whose sum is σ = 36906432. Its totient is φ = 9177840.

The previous prime is 21471839. The next prime is 21471883. The reversal of 21471842 is 24817412.

21471842 is nontrivially palindromic in base 6.

It is a super-2 number, since 2×21471842² = 922079997745928, which contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4073 + ... + 7715.

It is an arithmetic number, because the mean of its divisors is an integer number (2306652).

Almost surely, 2^21471842 is an apocalyptic number.

21471842 is a deficient number, since it is larger than the sum of its proper divisors (15434590).

21471842 is a wasteful number, since it uses less digits than its factorization.

21471842 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4073.

The product of its digits is 3584, while the sum is 29.

The square root of 21471842 is about 4633.7718977093. The cubic root of 21471842 is about 277.9434438027.

The spelling of 21471842 in words is "twenty-one million, four hundred seventy-one thousand, eight hundred forty-two".