770661 has 32 divisors (see below), whose sum is σ = 1278720. Its totient is φ = 456192.

The previous prime is 770657. The next prime is 770663. The reversal of 770661 is 166077.

770661 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

770661 is a nontrivial binomial coefficient, being equal to C(1242, 2).

It is not a de Polignac number, because 770661 - 2² = 770657 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (770663) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 10521 + ... + 10593.

It is an arithmetic number, because the mean of its divisors is an integer number (39960).

2⁷⁷⁰⁶⁶¹ is an apocalyptic number.

770661 is the 1241-st triangular number and also the 621-st hexagonal number.

It is an amenable number.

770661 is a deficient number, since it is larger than the sum of its proper divisors (508059).

770661 is a wasteful number, since it uses less digits than its factorization.

770661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 122 (or 116 counting only the distinct ones).

The product of its (nonzero) digits is 1764, while the sum is 27.

The square root of 770661 is about 877.8729976483. The cubic root of 770661 is about 91.6827843101.

It can be divided in two parts, 770 and 661, that added together give a triangular number (1431 = T₅₃).

The spelling of 770661 in words is "seven hundred seventy thousand, six hundred sixty-one".