161220587 has 4 divisors (see below), whose sum is σ = 175877016. Its totient is φ = 146564160.

The previous prime is 161220583. The next prime is 161220601. The reversal of 161220587 is 785022161.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 161220587 - 2² = 161220583 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (161220583) 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, 7328198 + ... + 7328219.

It is an arithmetic number, because the mean of its divisors is an integer number (43969254).

Almost surely, 2^161220587 is an apocalyptic number.

161220587 is a deficient number, since it is larger than the sum of its proper divisors (14656429).

161220587 is a wasteful number, since it uses less digits than its factorization.

161220587 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14656428.

The product of its (nonzero) digits is 6720, while the sum is 32.

The square root of 161220587 is about 12697.2669106387. The cubic root of 161220587 is about 544.2605205370.

The spelling of 161220587 in words is "one hundred sixty-one million, two hundred twenty thousand, five hundred eighty-seven".