7825991 has 2 divisors, whose sum is σ = 7825992. Its totient is φ = 7825990.

The previous prime is 7825973. The next prime is 7825997. The reversal of 7825991 is 1995287.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-7825991 is a prime.

It is a super-2 number, since 2×7825991² = 122492270264162, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (7825997) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3912995 + 3912996.

It is an arithmetic number, because the mean of its divisors is an integer number (3912996).

Almost surely, 2^7825991 is an apocalyptic number.

7825991 is a deficient number, since it is larger than the sum of its proper divisors (1).

7825991 is an equidigital number, since it uses as much as digits as its factorization.

7825991 is an evil number, because the sum of its binary digits is even.

The product of its digits is 45360, while the sum is 41.

The square root of 7825991 is about 2797.4972743508. The cubic root of 7825991 is about 198.5392824946.

The spelling of 7825991 in words is "seven million, eight hundred twenty-five thousand, nine hundred ninety-one".