72238421 has 2 divisors, whose sum is σ = 72238422. Its totient is φ = 72238420.

The previous prime is 72238381. The next prime is 72238427. The reversal of 72238421 is 12483227.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 68392900 + 3845521 = 8270^2 + 1961^2 .

It is a cyclic number.

It is not a de Polignac number, because 72238421 - 2²² = 68044117 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (72238427) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36119210 + 36119211.

It is an arithmetic number, because the mean of its divisors is an integer number (36119211).

Almost surely, 2^72238421 is an apocalyptic number.

It is an amenable number.

72238421 is a deficient number, since it is larger than the sum of its proper divisors (1).

72238421 is an equidigital number, since it uses as much as digits as its factorization.

72238421 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5376, while the sum is 29.

The square root of 72238421 is about 8499.3188550613. The cubic root of 72238421 is about 416.4754583657.

The spelling of 72238421 in words is "seventy-two million, two hundred thirty-eight thousand, four hundred twenty-one".