21374138 has 8 divisors (see below), whose sum is σ = 32087232. Its totient is φ = 10678396.

The previous prime is 21374113. The next prime is 21374147. The reversal of 21374138 is 83147312.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a self number, because there is not a number n which added to its sum of digits gives 21374138.

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 3 ways as a sum of consecutive naturals, for example, 620 + ... + 6567.

It is an arithmetic number, because the mean of its divisors is an integer number (4010904).

Almost surely, 2^21374138 is an apocalyptic number.

21374138 is a deficient number, since it is larger than the sum of its proper divisors (10713094).

21374138 is a wasteful number, since it uses less digits than its factorization.

21374138 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8676.

The product of its digits is 4032, while the sum is 29.

The square root of 21374138 is about 4623.2172780435. The cubic root of 21374138 is about 277.5212244676.

It can be divided in two parts, 21374 and 138, that added together give a palindrome (21512).

The spelling of 21374138 in words is "twenty-one million, three hundred seventy-four thousand, one hundred thirty-eight".