21152774 has 16 divisors (see below), whose sum is σ = 32976720. Its totient is φ = 10164000.

The previous prime is 21152759. The next prime is 21152783. The reversal of 21152774 is 47725112.

It is a Harshad number since it is a multiple of its sum of digits (29).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13832 + ... + 15284.

It is an arithmetic number, because the mean of its divisors is an integer number (2061045).

Almost surely, 2^21152774 is an apocalyptic number.

21152774 is a deficient number, since it is larger than the sum of its proper divisors (11823946).

21152774 is a wasteful number, since it uses less digits than its factorization.

21152774 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1735.

The product of its digits is 3920, while the sum is 29.

The square root of 21152774 is about 4599.2144981507. The cubic root of 21152774 is about 276.5598364985.

Adding to 21152774 its reverse (47725112), we get a palindrome (68877886).

The spelling of 21152774 in words is "twenty-one million, one hundred fifty-two thousand, seven hundred seventy-four".