161491357 has 8 divisors (see below), whose sum is σ = 163781856. Its totient is φ = 159209232.

The previous prime is 161491289. The next prime is 161491361. The reversal of 161491357 is 753194161.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 161491357 - 2²³ = 153102749 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161491367) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 43623 + ... + 47179.

It is an arithmetic number, because the mean of its divisors is an integer number (20472732).

Almost surely, 2^161491357 is an apocalyptic number.

It is an amenable number.

161491357 is a deficient number, since it is larger than the sum of its proper divisors (2290499).

161491357 is an equidigital number, since it uses as much as digits as its factorization.

161491357 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4187.

The product of its digits is 22680, while the sum is 37.

The square root of 161491357 is about 12707.9249683023. The cubic root of 161491357 is about 544.5650453260.

The spelling of 161491357 in words is "one hundred sixty-one million, four hundred ninety-one thousand, three hundred fifty-seven".