72434021 has 4 divisors (see below), whose sum is σ = 79018944. Its totient is φ = 65849100.

The previous prime is 72434009. The next prime is 72434041. The reversal of 72434021 is 12043427.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 72434021 - 2²⁶ = 5325157 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 (72434041) 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, 3292445 + ... + 3292466.

It is an arithmetic number, because the mean of its divisors is an integer number (19754736).

Almost surely, 2^72434021 is an apocalyptic number.

It is an amenable number.

72434021 is a deficient number, since it is larger than the sum of its proper divisors (6584923).

72434021 is a wasteful number, since it uses less digits than its factorization.

72434021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6584922.

The product of its (nonzero) digits is 1344, while the sum is 23.

The square root of 72434021 is about 8510.8178807915. The cubic root of 72434021 is about 416.8510165221.

Adding to 72434021 its reverse (12043427), we get a palindrome (84477448).

The spelling of 72434021 in words is "seventy-two million, four hundred thirty-four thousand, twenty-one".