21045734 has 4 divisors (see below), whose sum is σ = 31568604. Its totient is φ = 10522866.

The previous prime is 21045727. The next prime is 21045737. The reversal of 21045734 is 43754012.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21045737) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5261432 + ... + 5261435.

It is an arithmetic number, because the mean of its divisors is an integer number (7892151).

Almost surely, 2^21045734 is an apocalyptic number.

21045734 is a deficient number, since it is larger than the sum of its proper divisors (10522870).

21045734 is a wasteful number, since it uses less digits than its factorization.

21045734 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10522869.

The product of its (nonzero) digits is 3360, while the sum is 26.

The square root of 21045734 is about 4587.5629695951. The cubic root of 21045734 is about 276.0925528012.

Adding to 21045734 its reverse (43754012), we get a palindrome (64799746).

The spelling of 21045734 in words is "twenty-one million, forty-five thousand, seven hundred thirty-four".