72996421 has 2 divisors, whose sum is σ = 72996422. Its totient is φ = 72996420.

The previous prime is 72996397. The next prime is 72996431. The reversal of 72996421 is 12469927.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 38316100 + 34680321 = 6190^2 + 5889^2 .

It is a cyclic number.

It is not a de Polignac number, because 72996421 - 2⁷ = 72996293 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (72996431) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36498210 + 36498211.

It is an arithmetic number, because the mean of its divisors is an integer number (36498211).

Almost surely, 2^72996421 is an apocalyptic number.

It is an amenable number.

72996421 is a deficient number, since it is larger than the sum of its proper divisors (1).

72996421 is an equidigital number, since it uses as much as digits as its factorization.

72996421 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 54432, while the sum is 40.

The square root of 72996421 is about 8543.7942976174. The cubic root of 72996421 is about 417.9270894557.

The spelling of 72996421 in words is "seventy-two million, nine hundred ninety-six thousand, four hundred twenty-one".