21157476 has 24 divisors (see below), whose sum is σ = 50572704. Its totient is φ = 6880320.

The previous prime is 21157463. The next prime is 21157483. The reversal of 21157476 is 67475112.

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, 21010 + ... + 21993.

It is an arithmetic number, because the mean of its divisors is an integer number (2107196).

Almost surely, 2^21157476 is an apocalyptic number.

It is an amenable number.

21157476 is an abundant number, since it is smaller than the sum of its proper divisors (29415228).

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

21157476 is a wasteful number, since it uses less digits than its factorization.

21157476 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43051 (or 43049 counting only the distinct ones).

The product of its digits is 11760, while the sum is 33.

The square root of 21157476 is about 4599.7256439923. The cubic root of 21157476 is about 276.5803269239.

It can be divided in two parts, 2115 and 7476, that added together give a triangular number (9591 = T₁₃₈).

The spelling of 21157476 in words is "twenty-one million, one hundred fifty-seven thousand, four hundred seventy-six".