21402774 has 24 divisors (see below), whose sum is σ = 46519200. Its totient is φ = 7111728.

The previous prime is 21402763. The next prime is 21402817. The reversal of 21402774 is 47720412.

It is a happy number.

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 11 ways as a sum of consecutive naturals, for example, 4579 + ... + 7985.

It is an arithmetic number, because the mean of its divisors is an integer number (1938300).

Almost surely, 2^21402774 is an apocalyptic number.

21402774 is an abundant number, since it is smaller than the sum of its proper divisors (25116426).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21402774 is a wasteful number, since it uses less digits than its factorization.

21402774 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3764 (or 3761 counting only the distinct ones).

The product of its (nonzero) digits is 3136, while the sum is 27.

The square root of 21402774 is about 4626.3132189682. The cubic root of 21402774 is about 277.6451055083.

The spelling of 21402774 in words is "twenty-one million, four hundred two thousand, seven hundred seventy-four".