71998911 has 18 divisors (see below), whose sum is σ = 106619240. Its totient is φ = 46818720.

The previous prime is 71998907. The next prime is 71998921. The reversal of 71998911 is 11989917.

It is not a de Polignac number, because 71998911 - 2² = 71998907 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 (71998921) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 12750 + ... + 17508.

Almost surely, 2^71998911 is an apocalyptic number.

71998911 is a deficient number, since it is larger than the sum of its proper divisors (34620329).

71998911 is a wasteful number, since it uses less digits than its factorization.

71998911 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4847 (or 4803 counting only the distinct ones).

The product of its digits is 40824, while the sum is 45.

The square root of 71998911 is about 8485.2172040555. The cubic root of 71998911 is about 416.0146671820.

It can be divided in two parts, 7199 and 8911, that added together give a triangular number (16110 = T₁₇₉).

The spelling of 71998911 in words is "seventy-one million, nine hundred ninety-eight thousand, nine hundred eleven".