72206551 has 2 divisors, whose sum is σ = 72206552. Its totient is φ = 72206550.

The previous prime is 72206543. The next prime is 72206557. The reversal of 72206551 is 15560227.

It is a strong prime.

It is an emirp because it is prime and its reverse (15560227) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 72206551 - 2³ = 72206543 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (72206557) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36103275 + 36103276.

It is an arithmetic number, because the mean of its divisors is an integer number (36103276).

Almost surely, 2^72206551 is an apocalyptic number.

72206551 is a deficient number, since it is larger than the sum of its proper divisors (1).

72206551 is an equidigital number, since it uses as much as digits as its factorization.

72206551 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4200, while the sum is 28.

The square root of 72206551 is about 8497.4437921060. The cubic root of 72206551 is about 416.4142027574.

Adding to 72206551 its reverse (15560227), we get a palindrome (87766778).

The spelling of 72206551 in words is "seventy-two million, two hundred six thousand, five hundred fifty-one".