21060739 has 24 divisors (see below), whose sum is σ = 26273808. Its totient is φ = 16773120.

The previous prime is 21060731. The next prime is 21060751. The reversal of 21060739 is 93706012.

It is not a de Polignac number, because 21060739 - 2³ = 21060731 is a prime.

It is a super-2 number, since 2×21060739² = 887109454452242, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21060731) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 109027 + ... + 109219.

It is an arithmetic number, because the mean of its divisors is an integer number (1094742).

Almost surely, 2^21060739 is an apocalyptic number.

21060739 is a deficient number, since it is larger than the sum of its proper divisors (5213069).

21060739 is a wasteful number, since it uses less digits than its factorization.

21060739 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 355 (or 348 counting only the distinct ones).

The product of its (nonzero) digits is 2268, while the sum is 28.

The square root of 21060739 is about 4589.1980780960. The cubic root of 21060739 is about 276.1581525499.

The spelling of 21060739 in words is "twenty-one million, sixty thousand, seven hundred thirty-nine".