7903991 has 2 divisors, whose sum is σ = 7903992. Its totient is φ = 7903990.

The previous prime is 7903937. The next prime is 7903993. The reversal of 7903991 is 1993097.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 7903991 - 2¹⁸ = 7641847 is a prime.

Together with 7903993, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (7903993) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3951995 + 3951996.

It is an arithmetic number, because the mean of its divisors is an integer number (3951996).

Almost surely, 2^7903991 is an apocalyptic number.

7903991 is a deficient number, since it is larger than the sum of its proper divisors (1).

7903991 is an equidigital number, since it uses as much as digits as its factorization.

7903991 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 15309, while the sum is 38.

The square root of 7903991 is about 2811.4037419055. The cubic root of 7903991 is about 199.1967028884.

The spelling of 7903991 in words is "seven million, nine hundred three thousand, nine hundred ninety-one".