21001432 has 16 divisors (see below), whose sum is σ = 39450600. Its totient is φ = 10481280.

The previous prime is 21001429. The next prime is 21001447. The reversal of 21001432 is 23410012.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2832 + ... + 7072.

Almost surely, 2^21001432 is an apocalyptic number.

It is an amenable number.

21001432 is a deficient number, since it is larger than the sum of its proper divisors (18449168).

21001432 is a wasteful number, since it uses less digits than its factorization.

21001432 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4866 (or 4862 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 13.

The square root of 21001432 is about 4582.7319363018. The cubic root of 21001432 is about 275.8986885740.

Adding to 21001432 its reverse (23410012), we get a palindrome (44411444).

The spelling of 21001432 in words is "twenty-one million, one thousand, four hundred thirty-two".