117823521 has 4 divisors (see below), whose sum is σ = 157098032. Its totient is φ = 78549012.

The previous prime is 117823471. The next prime is 117823547. The reversal of 117823521 is 125328711.

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, and also an emirpimes, since its reverse is a distinct semiprime: 125328711 = 3 ⋅41776237.

It is not a de Polignac number, because 117823521 - 2¹³ = 117815329 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (117823571) 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, 19637251 + ... + 19637256.

It is an arithmetic number, because the mean of its divisors is an integer number (39274508).

Almost surely, 2^117823521 is an apocalyptic number.

It is an amenable number.

117823521 is a deficient number, since it is larger than the sum of its proper divisors (39274511).

117823521 is an equidigital number, since it uses as much as digits as its factorization.

117823521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39274510.

The product of its digits is 3360, while the sum is 30.

The square root of 117823521 is about 10854.6543473295. The cubic root of 117823521 is about 490.2421696182.

The spelling of 117823521 in words is "one hundred seventeen million, eight hundred twenty-three thousand, five hundred twenty-one".