21474164 has 6 divisors (see below), whose sum is σ = 37579794. Its totient is φ = 10737080.

The previous prime is 21474143. The next prime is 21474217. The reversal of 21474164 is 46147412.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 19891600 + 1582564 = 4460^2 + 1258^2 .

It is a super-2 number, since 2×21474164² = 922279438997792, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2684267 + ... + 2684274.

It is an arithmetic number, because the mean of its divisors is an integer number (6263299).

Almost surely, 2^21474164 is an apocalyptic number.

It is an amenable number.

21474164 is a deficient number, since it is larger than the sum of its proper divisors (16105630).

21474164 is a wasteful number, since it uses less digits than its factorization.

21474164 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5368545 (or 5368543 counting only the distinct ones).

The product of its digits is 5376, while the sum is 29.

The square root of 21474164 is about 4634.0224427596. The cubic root of 21474164 is about 277.9534625273.

The spelling of 21474164 in words is "twenty-one million, four hundred seventy-four thousand, one hundred sixty-four".