84851991 has 48 divisors (see below), whose sum is σ = 150958080. Its totient is φ = 44858880.

The previous prime is 84851969. The next prime is 84852017. The reversal of 84851991 is 19915848.

84851991 is a `hidden beast` number, since 8 + 48 + 519 + 91 = 666.

It is not a de Polignac number, because 84851991 - 2⁵ = 84851959 is a prime.

It is a hoax number, since the sum of its digits (45) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (84851911) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 43975 + ... + 45863.

It is an arithmetic number, because the mean of its divisors is an integer number (3144960).

Almost surely, 2^84851991 is an apocalyptic number.

84851991 is a deficient number, since it is larger than the sum of its proper divisors (66106089).

84851991 is a wasteful number, since it uses less digits than its factorization.

84851991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1956 (or 1953 counting only the distinct ones).

The product of its digits is 103680, while the sum is 45.

The square root of 84851991 is about 9211.5140449331. The cubic root of 84851991 is about 439.4276148810.

The spelling of 84851991 in words is "eighty-four million, eight hundred fifty-one thousand, nine hundred ninety-one".