83840991 has 16 divisors (see below), whose sum is σ = 127469664. Its totient is φ = 48559104.

The previous prime is 83840971. The next prime is 83840993. The reversal of 83840991 is 19904838.

It is not a de Polignac number, because 83840991 - 2¹³ = 83832799 is a prime.

It is a super-3 number, since 3×83840991³ (a number of 25 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (83840993) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 62566 + ... + 63891.

It is an arithmetic number, because the mean of its divisors is an integer number (7966854).

Almost surely, 2^83840991 is an apocalyptic number.

83840991 is a deficient number, since it is larger than the sum of its proper divisors (43628673).

83840991 is a wasteful number, since it uses less digits than its factorization.

83840991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 126490.

The product of its (nonzero) digits is 62208, while the sum is 42.

The square root of 83840991 is about 9156.4726286928. The cubic root of 83840991 is about 437.6753969924.

The spelling of 83840991 in words is "eighty-three million, eight hundred forty thousand, nine hundred ninety-one".