157368661 has 4 divisors (see below), whose sum is σ = 157397632. Its totient is φ = 157339692.

The previous prime is 157368649. The next prime is 157368671. The reversal of 157368661 is 166863751.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 166863751 = 1163 ⋅143477.

It is a 3-Lehmer number, since φ(157368661) divides (157368661-1)³.

It is a cyclic number.

It is not a de Polignac number, because 157368661 - 2¹⁷ = 157237589 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 (157368611) 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 3 ways as a sum of consecutive naturals, for example, 3621 + ... + 18106.

It is an arithmetic number, because the mean of its divisors is an integer number (39349408).

It is a Poulet number, since it divides 2^157368660-1.

Almost surely, 2^157368661 is an apocalyptic number.

157368661 is the 7243-rd octagonal number.

It is an amenable number.

157368661 is a deficient number, since it is larger than the sum of its proper divisors (28971).

157368661 is an equidigital number, since it uses as much as digits as its factorization.

157368661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28970.

The product of its digits is 181440, while the sum is 43.

The square root of 157368661 is about 12544.6666356663. Note that the first 4 decimals coincide. The cubic root of 157368661 is about 539.8909942296.

The spelling of 157368661 in words is "one hundred fifty-seven million, three hundred sixty-eight thousand, six hundred sixty-one".