21375734 has 4 divisors (see below), whose sum is σ = 32063604. Its totient is φ = 10687866.

The previous prime is 21375721. The next prime is 21375743. The reversal of 21375734 is 43757312.

It is a semiprime because it is the product of two primes.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 21375734.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5343932 + ... + 5343935.

It is an arithmetic number, because the mean of its divisors is an integer number (8015901).

Almost surely, 2^21375734 is an apocalyptic number.

21375734 is a deficient number, since it is larger than the sum of its proper divisors (10687870).

21375734 is a wasteful number, since it uses less digits than its factorization.

21375734 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10687869.

The product of its digits is 17640, while the sum is 32.

The square root of 21375734 is about 4623.3898818940. The cubic root of 21375734 is about 277.5281317691.

The spelling of 21375734 in words is "twenty-one million, three hundred seventy-five thousand, seven hundred thirty-four".