732400021 has 4 divisors (see below), whose sum is σ = 742432972. Its totient is φ = 722367072.

The previous prime is 732400007. The next prime is 732400027. The reversal of 732400021 is 120004237.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 528310225 + 204089796 = 22985^2 + 14286^2 .

It is a cyclic number.

It is not a de Polignac number, because 732400021 - 2⁵ = 732399989 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (732400027) 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, 5016366 + ... + 5016511.

It is an arithmetic number, because the mean of its divisors is an integer number (185608243).

Almost surely, 2^732400021 is an apocalyptic number.

It is an amenable number.

732400021 is a deficient number, since it is larger than the sum of its proper divisors (10032951).

732400021 is a wasteful number, since it uses less digits than its factorization.

732400021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10032950.

The product of its (nonzero) digits is 336, while the sum is 19.

The square root of 732400021 is about 27062.8901080428. The cubic root of 732400021 is about 901.3970159707.

Adding to 732400021 its reverse (120004237), we get a palindrome (852404258).

The spelling of 732400021 in words is "seven hundred thirty-two million, four hundred thousand, twenty-one".