611615993 has 2 divisors, whose sum is σ = 611615994. Its totient is φ = 611615992.

The previous prime is 611615981. The next prime is 611616001. The reversal of 611615993 is 399516116.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 594043129 + 17572864 = 24373^2 + 4192^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-611615993 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 611615993.

It is not a weakly prime, because it can be changed into another prime (611611993) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 305807996 + 305807997.

It is an arithmetic number, because the mean of its divisors is an integer number (305807997).

Almost surely, 2^611615993 is an apocalyptic number.

It is an amenable number.

611615993 is a deficient number, since it is larger than the sum of its proper divisors (1).

611615993 is an equidigital number, since it uses as much as digits as its factorization.

611615993 is an evil number, because the sum of its binary digits is even.

The product of its digits is 43740, while the sum is 41.

The square root of 611615993 is about 24730.8712543655. The cubic root of 611615993 is about 848.8408619954.

The spelling of 611615993 in words is "six hundred eleven million, six hundred fifteen thousand, nine hundred ninety-three".