161901586 has 48 divisors (see below), whose sum is σ = 311444352. Its totient is φ = 62412000.

The previous prime is 161901583. The next prime is 161901617. The reversal of 161901586 is 685109161.

It is not an unprimeable number, because it can be changed into a prime (161901583) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 108135 + ... + 109621.

It is an arithmetic number, because the mean of its divisors is an integer number (6488424).

Almost surely, 2^161901586 is an apocalyptic number.

161901586 is a deficient number, since it is larger than the sum of its proper divisors (149542766).

161901586 is a wasteful number, since it uses less digits than its factorization.

161901586 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1615 (or 1608 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 37.

The square root of 161901586 is about 12724.0554069840. The cubic root of 161901586 is about 545.0257665342.

The spelling of 161901586 in words is "one hundred sixty-one million, nine hundred one thousand, five hundred eighty-six".