946639991 has 6 divisors (see below), whose sum is σ = 1040521776. Its totient is φ = 860581700.

The previous prime is 946639909. The next prime is 946639999. The reversal of 946639991 is 199936649.

It is not a de Polignac number, because 946639991 - 2¹⁴ = 946623607 is a prime.

It is a super-2 number, since 2×946639991² = 1792254545120960162, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (946639999) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 3911615 + ... + 3911856.

It is an arithmetic number, because the mean of its divisors is an integer number (173420296).

Almost surely, 2^946639991 is an apocalyptic number.

946639991 is a deficient number, since it is larger than the sum of its proper divisors (93881785).

946639991 is a wasteful number, since it uses less digits than its factorization.

946639991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7823493 (or 7823482 counting only the distinct ones).

The product of its digits is 2834352, while the sum is 56.

The square root of 946639991 is about 30767.5151905382. The cubic root of 946639991 is about 981.8872389857.

The spelling of 946639991 in words is "nine hundred forty-six million, six hundred thirty-nine thousand, nine hundred ninety-one".