117887921 has 2 divisors, whose sum is σ = 117887922. Its totient is φ = 117887920.

The previous prime is 117887899. The next prime is 117887933. The reversal of 117887921 is 129788711.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 62236321 + 55651600 = 7889^2 + 7460^2 .

It is a cyclic number.

It is not a de Polignac number, because 117887921 - 2²² = 113693617 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (117887221) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 58943960 + 58943961.

It is an arithmetic number, because the mean of its divisors is an integer number (58943961).

Almost surely, 2^117887921 is an apocalyptic number.

It is an amenable number.

117887921 is a deficient number, since it is larger than the sum of its proper divisors (1).

117887921 is an equidigital number, since it uses as much as digits as its factorization.

117887921 is an evil number, because the sum of its binary digits is even.

The product of its digits is 56448, while the sum is 44.

The square root of 117887921 is about 10857.6204114898. The cubic root of 117887921 is about 490.3314722325.

The spelling of 117887921 in words is "one hundred seventeen million, eight hundred eighty-seven thousand, nine hundred twenty-one".