71899491 has 4 divisors (see below), whose sum is σ = 95865992. Its totient is φ = 47932992.

The previous prime is 71899469. The next prime is 71899493. The reversal of 71899491 is 19499817.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 19499817 = 3 ⋅6499939.

It is not a de Polignac number, because 71899491 - 2⁹ = 71898979 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 71899491.

It is not an unprimeable number, because it can be changed into a prime (71899493) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11983246 + ... + 11983251.

It is an arithmetic number, because the mean of its divisors is an integer number (23966498).

Almost surely, 2^71899491 is an apocalyptic number.

71899491 is a deficient number, since it is larger than the sum of its proper divisors (23966501).

71899491 is a wasteful number, since it uses less digits than its factorization.

71899491 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23966500.

The product of its digits is 163296, while the sum is 48.

The square root of 71899491 is about 8479.3567562640. The cubic root of 71899491 is about 415.8230937738.

It can be divided in two parts, 71899 and 491, that added together give a triangular number (72390 = T₃₈₀).

The spelling of 71899491 in words is "seventy-one million, eight hundred ninety-nine thousand, four hundred ninety-one".