21990152 has 8 divisors (see below), whose sum is σ = 41231550. Its totient is φ = 10995072.

The previous prime is 21990131. The next prime is 21990169. The reversal of 21990152 is 25109912.

It can be written as a sum of positive squares in only one way, i.e., 20124196 + 1865956 = 4486^2 + 1366^2 .

It is a tau number, because it is divible by the number of its divisors (8).

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 as a sum of consecutive naturals, namely, 1374377 + ... + 1374392.

Almost surely, 2^21990152 is an apocalyptic number.

It is an amenable number.

21990152 is a deficient number, since it is larger than the sum of its proper divisors (19241398).

21990152 is a wasteful number, since it uses less digits than its factorization.

21990152 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2748775 (or 2748771 counting only the distinct ones).

The product of its (nonzero) digits is 1620, while the sum is 29.

The square root of 21990152 is about 4689.3658419876. The cubic root of 21990152 is about 280.1621170022.

The spelling of 21990152 in words is "twenty-one million, nine hundred ninety thousand, one hundred fifty-two".