776991 has 8 divisors (see below), whose sum is σ = 1061424. Its totient is φ = 505280.

The previous prime is 776987. The next prime is 777001. The reversal of 776991 is 199677.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 776991 - 2² = 776987 is a prime.

776991 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (776921) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3036 + ... + 3281.

It is an arithmetic number, because the mean of its divisors is an integer number (132678).

2⁷⁷⁶⁹⁹¹ is an apocalyptic number.

776991 is a deficient number, since it is larger than the sum of its proper divisors (284433).

776991 is a wasteful number, since it uses less digits than its factorization.

776991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6361.

The product of its digits is 23814, while the sum is 39.

The square root of 776991 is about 881.4709297532. The cubic root of 776991 is about 91.9331193188.

The spelling of 776991 in words is "seven hundred seventy-six thousand, nine hundred ninety-one".