72216631 has 2 divisors, whose sum is σ = 72216632. Its totient is φ = 72216630.

The previous prime is 72216541. The next prime is 72216643. The reversal of 72216631 is 13661227.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 72216631 - 2¹³ = 72208439 is a prime.

It is a super-2 number, since 2×72216631² = 10430483585980322, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 72216631.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (72216671) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36108315 + 36108316.

It is an arithmetic number, because the mean of its divisors is an integer number (36108316).

Almost surely, 2^72216631 is an apocalyptic number.

72216631 is a deficient number, since it is larger than the sum of its proper divisors (1).

72216631 is an equidigital number, since it uses as much as digits as its factorization.

72216631 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3024, while the sum is 28.

The square root of 72216631 is about 8498.0368909531. The cubic root of 72216631 is about 416.4335789303.

Adding to 72216631 its reverse (13661227), we get a palindrome (85877858).

The spelling of 72216631 in words is "seventy-two million, two hundred sixteen thousand, six hundred thirty-one".