161613638 has 8 divisors (see below), whose sum is σ = 243200880. Its totient is φ = 80546680.

The previous prime is 161613623. The next prime is 161613643. The reversal of 161613638 is 836316161.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×161613638² = 52237935975190088, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 161613598 and 161613607.

It is a congruent number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 129293 + ... + 130536.

It is an arithmetic number, because the mean of its divisors is an integer number (30400110).

Almost surely, 2^161613638 is an apocalyptic number.

161613638 is a deficient number, since it is larger than the sum of its proper divisors (81587242).

161613638 is a wasteful number, since it uses less digits than its factorization.

161613638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 260142.

The product of its digits is 15552, while the sum is 35.

The square root of 161613638 is about 12712.7352682261. The cubic root of 161613638 is about 544.7024585790.

Adding to 161613638 its reverse (836316161), we get a palindrome (997929799).

The spelling of 161613638 in words is "one hundred sixty-one million, six hundred thirteen thousand, six hundred thirty-eight".