117721647 has 8 divisors (see below), whose sum is σ = 174402480. Its totient is φ = 78481080.

The previous prime is 117721631. The next prime is 117721673. The reversal of 117721647 is 746127711.

117721647 is a `hidden beast` number, since 1 + 1 + 7 + 7 + 2 + 1 + 647 = 666.

It is not a de Polignac number, because 117721647 - 2⁴ = 117721631 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (117721847) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2180004 + ... + 2180057.

It is an arithmetic number, because the mean of its divisors is an integer number (21800310).

Almost surely, 2^117721647 is an apocalyptic number.

117721647 is a deficient number, since it is larger than the sum of its proper divisors (56680833).

117721647 is an equidigital number, since it uses as much as digits as its factorization.

117721647 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4360070 (or 4360064 counting only the distinct ones).

The product of its digits is 16464, while the sum is 36.

The square root of 117721647 is about 10849.9606911730. The cubic root of 117721647 is about 490.1008358354.

The spelling of 117721647 in words is "one hundred seventeen million, seven hundred twenty-one thousand, six hundred forty-seven".