21025832 has 8 divisors (see below), whose sum is σ = 39423450. Its totient is φ = 10512912.

The previous prime is 21025831. The next prime is 21025861. The reversal of 21025832 is 23852012.

It can be written as a sum of positive squares in only one way, i.e., 20376196 + 649636 = 4514^2 + 806^2 .

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

It is a super-2 number, since 2×21025832² = 884171222584448, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21025798 and 21025807.

It is not an unprimeable number, because it can be changed into a prime (21025831) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1314107 + ... + 1314122.

Almost surely, 2^21025832 is an apocalyptic number.

It is an amenable number.

21025832 is a deficient number, since it is larger than the sum of its proper divisors (18397618).

21025832 is a wasteful number, since it uses less digits than its factorization.

21025832 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2628235 (or 2628231 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 23.

The square root of 21025832 is about 4585.3933310023. The cubic root of 21025832 is about 276.0054959348.

Adding to 21025832 its reverse (23852012), we get a palindrome (44877844).

The spelling of 21025832 in words is "twenty-one million, twenty-five thousand, eight hundred thirty-two".