21472866 has 12 divisors (see below), whose sum is σ = 46524582. Its totient is φ = 7157616.

The previous prime is 21472849. The next prime is 21472879. The reversal of 21472866 is 66827412.

It can be written as a sum of positive squares in only one way, i.e., 15046641 + 6426225 = 3879^2 + 2535^2 .

It is a super-2 number, since 2×21472866² = 922167948507912, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21472866.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 596451 + ... + 596486.

Almost surely, 2^21472866 is an apocalyptic number.

21472866 is an abundant number, since it is smaller than the sum of its proper divisors (25051716).

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

21472866 is a wasteful number, since it uses less digits than its factorization.

21472866 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1192945 (or 1192942 counting only the distinct ones).

The product of its digits is 32256, while the sum is 36.

The square root of 21472866 is about 4633.8823895304. The cubic root of 21472866 is about 277.9478621406.

The spelling of 21472866 in words is "twenty-one million, four hundred seventy-two thousand, eight hundred sixty-six".