870921871 has 12 divisors (see below), whose sum is σ = 901654072. Its totient is φ = 840780864.

The previous prime is 870921859. The next prime is 870921893. The reversal of 870921871 is 178129078.

It is a happy number.

It is not a de Polignac number, because 870921871 - 2⁵ = 870921839 is a prime.

It is a super-2 number, since 2×870921871² = 1517009810772281282, which contains 22 as substring.

It is a hoax number, since the sum of its digits (43) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (43).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (870921671) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 339325 + ... + 341881.

Almost surely, 2^870921871 is an apocalyptic number.

870921871 is a deficient number, since it is larger than the sum of its proper divisors (30732201).

870921871 is an equidigital number, since it uses as much as digits as its factorization.

870921871 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2778 (or 2689 counting only the distinct ones).

The product of its (nonzero) digits is 56448, while the sum is 43.

The square root of 870921871 is about 29511.3854469762. The cubic root of 870921871 is about 954.9773378027.

The spelling of 870921871 in words is "eight hundred seventy million, nine hundred twenty-one thousand, eight hundred seventy-one".