161387917 has 4 divisors (see below), whose sum is σ = 162658816. Its totient is φ = 160117020.

The previous prime is 161387909. The next prime is 161387923. The reversal of 161387917 is 719783161.

It is a happy number.

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.

It is a cyclic number.

It is not a de Polignac number, because 161387917 - 2³ = 161387909 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161381917) 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, 635259 + ... + 635512.

It is an arithmetic number, because the mean of its divisors is an integer number (40664704).

Almost surely, 2^161387917 is an apocalyptic number.

It is an amenable number.

161387917 is a deficient number, since it is larger than the sum of its proper divisors (1270899).

161387917 is a wasteful number, since it uses less digits than its factorization.

161387917 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1270898.

The product of its digits is 63504, while the sum is 43.

The square root of 161387917 is about 12703.8544150978. The cubic root of 161387917 is about 544.4487504758.

The spelling of 161387917 in words is "one hundred sixty-one million, three hundred eighty-seven thousand, nine hundred seventeen".