21154694 has 16 divisors (see below), whose sum is σ = 34687440. Its totient is φ = 9596160.

The previous prime is 21154673. The next prime is 21154709. The reversal of 21154694 is 49645112.

It is a self number, because there is not a number n which added to its sum of digits gives 21154694.

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, 20462 + ... + 21470.

It is an arithmetic number, because the mean of its divisors is an integer number (2167965).

Almost surely, 2^21154694 is an apocalyptic number.

21154694 is a deficient number, since it is larger than the sum of its proper divisors (13532746).

21154694 is a wasteful number, since it uses less digits than its factorization.

21154694 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1975.

The product of its digits is 8640, while the sum is 32.

The square root of 21154694 is about 4599.4232247098. The cubic root of 21154694 is about 276.5682038616.

The spelling of 21154694 in words is "twenty-one million, one hundred fifty-four thousand, six hundred ninety-four".