771871681 has 4 divisors (see below), whose sum is σ = 882139072. Its totient is φ = 661604292.

The previous prime is 771871673. The next prime is 771871687. The reversal of 771871681 is 186178177.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 771871681 - 2³ = 771871673 is a prime.

It is a super-2 number, since 2×771871681² = 1191571783859531522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (771871687) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 55133685 + ... + 55133698.

It is an arithmetic number, because the mean of its divisors is an integer number (220534768).

Almost surely, 2^771871681 is an apocalyptic number.

It is an amenable number.

771871681 is a deficient number, since it is larger than the sum of its proper divisors (110267391).

771871681 is a wasteful number, since it uses less digits than its factorization.

771871681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 110267390.

The product of its digits is 131712, while the sum is 46.

The square root of 771871681 is about 27782.5787320040. The cubic root of 771871681 is about 917.3076932150.

The spelling of 771871681 in words is "seven hundred seventy-one million, eight hundred seventy-one thousand, six hundred eighty-one".