21040552 has 32 divisors (see below), whose sum is σ = 42688800. Its totient is φ = 9664704.

The previous prime is 21040549. The next prime is 21040559. The reversal of 21040552 is 25504012.

It is not an unprimeable number, because it can be changed into a prime (21040559) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 31599 + ... + 32257.

It is an arithmetic number, because the mean of its divisors is an integer number (1334025).

Almost surely, 2^21040552 is an apocalyptic number.

It is an amenable number.

21040552 is an abundant number, since it is smaller than the sum of its proper divisors (21648248).

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

21040552 is a wasteful number, since it uses less digits than its factorization.

21040552 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 985 (or 981 counting only the distinct ones).

The product of its (nonzero) digits is 400, while the sum is 19.

The square root of 21040552 is about 4586.9981469366. The cubic root of 21040552 is about 276.0698905829.

Adding to 21040552 its reverse (25504012), we get a palindrome (46544564).

The spelling of 21040552 in words is "twenty-one million, forty thousand, five hundred fifty-two".