71991453 has 4 divisors (see below), whose sum is σ = 95988608. Its totient is φ = 47994300.

The previous prime is 71991431. The next prime is 71991467. The reversal of 71991453 is 35419917.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 71991453 - 2⁶ = 71991389 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (71991553) 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, 11998573 + ... + 11998578.

It is an arithmetic number, because the mean of its divisors is an integer number (23997152).

Almost surely, 2^71991453 is an apocalyptic number.

It is an amenable number.

71991453 is a deficient number, since it is larger than the sum of its proper divisors (23997155).

71991453 is a wasteful number, since it uses less digits than its factorization.

71991453 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23997154.

The product of its digits is 34020, while the sum is 39.

The square root of 71991453 is about 8484.7777224863. Note that the first 4 decimals coincide. The cubic root of 71991453 is about 416.0003024067. Note that the first 3 decimals are identical.

The spelling of 71991453 in words is "seventy-one million, nine hundred ninety-one thousand, four hundred fifty-three".