7615991 has 2 divisors, whose sum is σ = 7615992. Its totient is φ = 7615990.

The previous prime is 7615981. The next prime is 7615999. The reversal of 7615991 is 1995167.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 7615991 - 2¹⁰ = 7614967 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (7615999) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3807995 + 3807996.

It is an arithmetic number, because the mean of its divisors is an integer number (3807996).

Almost surely, 2^7615991 is an apocalyptic number.

7615991 is a deficient number, since it is larger than the sum of its proper divisors (1).

7615991 is an equidigital number, since it uses as much as digits as its factorization.

7615991 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 17010, while the sum is 38.

The square root of 7615991 is about 2759.7084990991. The cubic root of 7615991 is about 196.7473118780.

The spelling of 7615991 in words is "seven million, six hundred fifteen thousand, nine hundred ninety-one".