117647681 has 4 divisors (see below), whose sum is σ = 117669552. Its totient is φ = 117625812.

The previous prime is 117647671. The next prime is 117647683. The reversal of 117647681 is 186746711.

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: 186746711 = 977 ⋅191143.

It is a cyclic number.

It is not a de Polignac number, because 117647681 - 2⁶ = 117647617 is a prime.

It is a super-2 number, since 2×117647681² = 27681953689355522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (117647683) 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, 3386 + ... + 15708.

It is an arithmetic number, because the mean of its divisors is an integer number (29417388).

Almost surely, 2^117647681 is an apocalyptic number.

It is an amenable number.

117647681 is a deficient number, since it is larger than the sum of its proper divisors (21871).

117647681 is an equidigital number, since it uses as much as digits as its factorization.

117647681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21870.

The product of its digits is 56448, while the sum is 41.

The square root of 117647681 is about 10846.5515718130. The cubic root of 117647681 is about 489.9981688117.

The spelling of 117647681 in words is "one hundred seventeen million, six hundred forty-seven thousand, six hundred eighty-one".