401767991 has 2 divisors, whose sum is σ = 401767992. Its totient is φ = 401767990.

The previous prime is 401767969. The next prime is 401768023. The reversal of 401767991 is 199767104.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-401767991 is a prime.

It is a super-2 number, since 2×401767991² = 322835037184352162, which contains 22 as substring.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (401767291) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 200883995 + 200883996.

It is an arithmetic number, because the mean of its divisors is an integer number (200883996).

Almost surely, 2^401767991 is an apocalyptic number.

401767991 is a deficient number, since it is larger than the sum of its proper divisors (1).

401767991 is an equidigital number, since it uses as much as digits as its factorization.

401767991 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 95256, while the sum is 44.

The square root of 401767991 is about 20044.1510421370. The cubic root of 401767991 is about 737.8902600221.

The spelling of 401767991 in words is "four hundred one million, seven hundred sixty-seven thousand, nine hundred ninety-one".