21061748 has 12 divisors (see below), whose sum is σ = 37302720. Its totient is φ = 10403832.

The previous prime is 21061739. The next prime is 21061757. The reversal of 21061748 is 84716012.

It is an interprime number because it is at equal distance from previous prime (21061739) and next prime (21061757).

It is a self number, because there is not a number n which added to its sum of digits gives 21061748.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 31388 + ... + 32051.

It is an arithmetic number, because the mean of its divisors is an integer number (3108560).

Almost surely, 2^21061748 is an apocalyptic number.

It is an amenable number.

21061748 is a deficient number, since it is larger than the sum of its proper divisors (16240972).

21061748 is a wasteful number, since it uses less digits than its factorization.

21061748 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 63526 (or 63524 counting only the distinct ones).

The product of its (nonzero) digits is 2688, while the sum is 29.

The square root of 21061748 is about 4589.3080088397. The cubic root of 21061748 is about 276.1625626377.

The spelling of 21061748 in words is "twenty-one million, sixty-one thousand, seven hundred forty-eight".