72206639 has 2 divisors, whose sum is σ = 72206640. Its totient is φ = 72206638.

The previous prime is 72206609. The next prime is 72206653. The reversal of 72206639 is 93660227.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-72206639 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 72206599 and 72206608.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (72206609) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36103319 + 36103320.

It is an arithmetic number, because the mean of its divisors is an integer number (36103320).

Almost surely, 2^72206639 is an apocalyptic number.

72206639 is a deficient number, since it is larger than the sum of its proper divisors (1).

72206639 is an equidigital number, since it uses as much as digits as its factorization.

72206639 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 27216, while the sum is 35.

The square root of 72206639 is about 8497.4489701322. The cubic root of 72206639 is about 416.4143719223.

The spelling of 72206639 in words is "seventy-two million, two hundred six thousand, six hundred thirty-nine".