161636397 has 16 divisors (see below), whose sum is σ = 235901568. Its totient is φ = 97836480.

The previous prime is 161636389. The next prime is 161636407. The reversal of 161636397 is 793636161.

It is not a de Polignac number, because 161636397 - 2³ = 161636389 is a prime.

It is a super-2 number, since 2×161636397² = 52252649670283218, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161636347) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 31593 + ... + 36350.

It is an arithmetic number, because the mean of its divisors is an integer number (14743848).

Almost surely, 2^161636397 is an apocalyptic number.

It is an amenable number.

161636397 is a deficient number, since it is larger than the sum of its proper divisors (74265171).

161636397 is a wasteful number, since it uses less digits than its factorization.

161636397 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 68020.

The product of its digits is 122472, while the sum is 42.

The square root of 161636397 is about 12713.6303627249. The cubic root of 161636397 is about 544.7280263499.

The spelling of 161636397 in words is "one hundred sixty-one million, six hundred thirty-six thousand, three hundred ninety-seven".