73215431 has 2 divisors, whose sum is σ = 73215432. Its totient is φ = 73215430.

The previous prime is 73215427. The next prime is 73215437. The reversal of 73215431 is 13451237.

It is a weak prime.

It is an emirp because it is prime and its reverse (13451237) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 73215431 - 2² = 73215427 is a prime.

It is a super-2 number, since 2×73215431² = 10720998673031522, which contains 22 as substring.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 73215431.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (73215437) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36607715 + 36607716.

It is an arithmetic number, because the mean of its divisors is an integer number (36607716).

Almost surely, 2^73215431 is an apocalyptic number.

73215431 is a deficient number, since it is larger than the sum of its proper divisors (1).

73215431 is an equidigital number, since it uses as much as digits as its factorization.

73215431 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2520, while the sum is 26.

The square root of 73215431 is about 8556.6016034405. The cubic root of 73215431 is about 418.3446388095.

Adding to 73215431 its reverse (13451237), we get a palindrome (86666668).

The spelling of 73215431 in words is "seventy-three million, two hundred fifteen thousand, four hundred thirty-one".