72661397 has 2 divisors, whose sum is σ = 72661398. Its totient is φ = 72661396.

The previous prime is 72661367. The next prime is 72661403. The reversal of 72661397 is 79316627.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 57365476 + 15295921 = 7574^2 + 3911^2 .

It is a cyclic number.

It is not a de Polignac number, because 72661397 - 2¹² = 72657301 is a prime.

It is a super-2 number, since 2×72661397² = 10559357227983218, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (72661367) 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, 36330698 + 36330699.

It is an arithmetic number, because the mean of its divisors is an integer number (36330699).

Almost surely, 2^72661397 is an apocalyptic number.

It is an amenable number.

72661397 is a deficient number, since it is larger than the sum of its proper divisors (1).

72661397 is an equidigital number, since it uses as much as digits as its factorization.

72661397 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 95256, while the sum is 41.

The square root of 72661397 is about 8524.1654723498. The cubic root of 72661397 is about 417.2867367913.

The spelling of 72661397 in words is "seventy-two million, six hundred sixty-one thousand, three hundred ninety-seven".