4991643766 has 4 divisors (see below), whose sum is σ = 7487465652. Its totient is φ = 2495821882.

The previous prime is 4991643757. The next prime is 4991643799. The reversal of 4991643766 is 6673461994.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 6673461994 = 2 ⋅3336730997.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1247910940 + ... + 1247910943.

It is an arithmetic number, because the mean of its divisors is an integer number (1871866413).

Almost surely, 2^4991643766 is an apocalyptic number.

4991643766 is a deficient number, since it is larger than the sum of its proper divisors (2495821886).

4991643766 is a wasteful number, since it uses less digits than its factorization.

4991643766 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2495821885.

The product of its digits is 5878656, while the sum is 55.

The square root of 4991643766 is about 70651.5659132903. The cubic root of 4991643766 is about 1709.0228182321.

The spelling of 4991643766 in words is "four billion, nine hundred ninety-one million, six hundred forty-three thousand, seven hundred sixty-six".