117661787 has 6 divisors (see below), whose sum is σ = 121859868. Its totient is φ = 113603672.

The previous prime is 117661781. The next prime is 117661793. The reversal of 117661787 is 787166711.

It is an interprime number because it is at equal distance from previous prime (117661781) and next prime (117661793).

It is not a de Polignac number, because 117661787 - 2⁶ = 117661723 is a prime.

It is a super-2 number, since 2×117661787² = 27688592240066738, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (117661781) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 69113 + ... + 70794.

It is an arithmetic number, because the mean of its divisors is an integer number (20309978).

Almost surely, 2^117661787 is an apocalyptic number.

117661787 is a deficient number, since it is larger than the sum of its proper divisors (4198081).

117661787 is an equidigital number, since it uses as much as digits as its factorization.

117661787 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 139965 (or 139936 counting only the distinct ones).

The product of its digits is 98784, while the sum is 44.

The square root of 117661787 is about 10847.2018050740. The cubic root of 117661787 is about 490.0177516823.

The spelling of 117661787 in words is "one hundred seventeen million, six hundred sixty-one thousand, seven hundred eighty-seven".