71533551 has 4 divisors (see below), whose sum is σ = 95378072. Its totient is φ = 47689032.

The previous prime is 71533549. The next prime is 71533601. The reversal of 71533551 is 15533517.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 71533551 - 2¹ = 71533549 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 (71533531) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11922256 + ... + 11922261.

It is an arithmetic number, because the mean of its divisors is an integer number (23844518).

Almost surely, 2^71533551 is an apocalyptic number.

71533551 is a deficient number, since it is larger than the sum of its proper divisors (23844521).

71533551 is a wasteful number, since it uses less digits than its factorization.

71533551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23844520.

The product of its digits is 7875, while the sum is 30.

The square root of 71533551 is about 8457.7509421832. The cubic root of 71533551 is about 415.1164351280.

The spelling of 71533551 in words is "seventy-one million, five hundred thirty-three thousand, five hundred fifty-one".