21029952 has 84 divisors (see below), whose sum is σ = 59263280. Its totient is φ = 6580224.

The previous prime is 21029951. The next prime is 21029971. The reversal of 21029952 is 25992012.

It is a super-2 number, since 2×21029952² = 884517762244608, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21029951) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 55299 + ... + 55677.

Almost surely, 2^21029952 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21029952, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29631640).

21029952 is an abundant number, since it is smaller than the sum of its proper divisors (38233328).

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

21029952 is a wasteful number, since it uses less digits than its factorization.

21029952 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 428 (or 401 counting only the distinct ones).

The product of its (nonzero) digits is 3240, while the sum is 30.

The square root of 21029952 is about 4585.8425616238. The cubic root of 21029952 is about 276.0235224649.

The spelling of 21029952 in words is "twenty-one million, twenty-nine thousand, nine hundred fifty-two".