72406643 has 2 divisors, whose sum is σ = 72406644. Its totient is φ = 72406642.

The previous prime is 72406613. The next prime is 72406651. The reversal of 72406643 is 34660427.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-72406643 is a prime.

It is a Sophie Germain prime.

It is equal to p_4251299 and since 72406643 and 4251299 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (72406613) 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, 36203321 + 36203322.

It is an arithmetic number, because the mean of its divisors is an integer number (36203322).

Almost surely, 2^72406643 is an apocalyptic number.

72406643 is a deficient number, since it is larger than the sum of its proper divisors (1).

72406643 is an equidigital number, since it uses as much as digits as its factorization.

72406643 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 24192, while the sum is 32.

The square root of 72406643 is about 8509.2093052175. The cubic root of 72406643 is about 416.7984906272.

The spelling of 72406643 in words is "seventy-two million, four hundred six thousand, six hundred forty-three".