21047952 has 20 divisors (see below), whose sum is σ = 54374000. Its totient is φ = 7015968.

The previous prime is 21047951. The next prime is 21047969. The reversal of 21047952 is 25974012.

It is not an unprimeable number, because it can be changed into a prime (21047951) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 219202 + ... + 219297.

It is an arithmetic number, because the mean of its divisors is an integer number (2718700).

Almost surely, 2^21047952 is an apocalyptic number.

It is an amenable number.

21047952 is an abundant number, since it is smaller than the sum of its proper divisors (33326048).

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

21047952 is a wasteful number, since it uses less digits than its factorization.

21047952 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 438510 (or 438504 counting only the distinct ones).

The product of its (nonzero) digits is 5040, while the sum is 30.

The square root of 21047952 is about 4587.8047037772. The cubic root of 21047952 is about 276.1022515485.

The spelling of 21047952 in words is "twenty-one million, forty-seven thousand, nine hundred fifty-two".