1630946991 has 4 divisors (see below), whose sum is σ = 2174595992. Its totient is φ = 1087297992.

The previous prime is 1630946963. The next prime is 1630947007. The reversal of 1630946991 is 1996490361.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 1630946991 - 2⁵ = 1630946959 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1630946991.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1630947991) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 271824496 + ... + 271824501.

It is an arithmetic number, because the mean of its divisors is an integer number (543648998).

Almost surely, 2^1630946991 is an apocalyptic number.

1630946991 is a deficient number, since it is larger than the sum of its proper divisors (543649001).

1630946991 is an equidigital number, since it uses as much as digits as its factorization.

1630946991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 543649000.

The product of its (nonzero) digits is 314928, while the sum is 48.

The square root of 1630946991 is about 40384.9847220474. The cubic root of 1630946991 is about 1177.0997892529.

The spelling of 1630946991 in words is "one billion, six hundred thirty million, nine hundred forty-six thousand, nine hundred ninety-one".