161513997 has 4 divisors (see below), whose sum is σ = 215352000. Its totient is φ = 107675996.

The previous prime is 161513983. The next prime is 161514007. The reversal of 161513997 is 799315161.

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 161513997 - 2¹⁴ = 161497613 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161517997) 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, 26918997 + ... + 26919002.

It is an arithmetic number, because the mean of its divisors is an integer number (53838000).

Almost surely, 2^161513997 is an apocalyptic number.

It is an amenable number.

161513997 is a deficient number, since it is larger than the sum of its proper divisors (53838003).

161513997 is an equidigital number, since it uses as much as digits as its factorization.

161513997 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 53838002.

The product of its digits is 51030, while the sum is 42.

The square root of 161513997 is about 12708.8157198065. The cubic root of 161513997 is about 544.5904922534.

The spelling of 161513997 in words is "one hundred sixty-one million, five hundred thirteen thousand, nine hundred ninety-seven".