877868861509 has 4 divisors (see below), whose sum is σ = 878048868204. Its totient is φ = 877688854816.

The previous prime is 877868861473. The next prime is 877868861521. The reversal of 877868861509 is 905168868778.

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

It can be written as a sum of positive squares in 2 ways, for example, as 112961193409 + 764907668100 = 336097^2 + 874590^2 .

It is a cyclic number.

It is not a de Polignac number, because 877868861509 - 2⁷ = 877868861381 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (877868865509) 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, 89996032 + ... + 90005785.

It is an arithmetic number, because the mean of its divisors is an integer number (219512217051).

Almost surely, 2^877868861509 is an apocalyptic number.

It is an amenable number.

877868861509 is a deficient number, since it is larger than the sum of its proper divisors (180006695).

877868861509 is a wasteful number, since it uses less digits than its factorization.

877868861509 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 180006694.

The product of its (nonzero) digits is 325140480, while the sum is 73.

The spelling of 877868861509 in words is "eight hundred seventy-seven billion, eight hundred sixty-eight million, eight hundred sixty-one thousand, five hundred nine".