215549797 has 2 divisors, whose sum is σ = 215549798. Its totient is φ = 215549796.

The previous prime is 215549773. The next prime is 215549819. The reversal of 215549797 is 797945512.

It is a happy number.

215549797 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 205091041 + 10458756 = 14321^2 + 3234^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-215549797 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 215549797.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (215549297) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 107774898 + 107774899.

It is an arithmetic number, because the mean of its divisors is an integer number (107774899).

Almost surely, 2^215549797 is an apocalyptic number.

It is an amenable number.

215549797 is a deficient number, since it is larger than the sum of its proper divisors (1).

215549797 is an equidigital number, since it uses as much as digits as its factorization.

215549797 is an evil number, because the sum of its binary digits is even.

The product of its digits is 793800, while the sum is 49.

The square root of 215549797 is about 14681.6142504835. The cubic root of 215549797 is about 599.5828554216.

The spelling of 215549797 in words is "two hundred fifteen million, five hundred forty-nine thousand, seven hundred ninety-seven".