21013694 has 16 divisors (see below), whose sum is σ = 34021680. Its totient is φ = 9676800.

The previous prime is 21013633. The next prime is 21013709. The reversal of 21013694 is 49631012.

It is a Harshad number since it is a multiple of its sum of digits (26).

It is a congruent number.

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 7 ways as a sum of consecutive naturals, for example, 19469 + ... + 20519.

It is an arithmetic number, because the mean of its divisors is an integer number (2126355).

Almost surely, 2^21013694 is an apocalyptic number.

21013694 is a deficient number, since it is larger than the sum of its proper divisors (13007986).

21013694 is a wasteful number, since it uses less digits than its factorization.

21013694 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1835.

The product of its (nonzero) digits is 1296, while the sum is 26.

The square root of 21013694 is about 4584.0695893496. The cubic root of 21013694 is about 275.9523739848.

The spelling of 21013694 in words is "twenty-one million, thirteen thousand, six hundred ninety-four".