157993393 has 4 divisors (see below), whose sum is σ = 167287140. Its totient is φ = 148699648.

The previous prime is 157993373. The next prime is 157993397. The reversal of 157993393 is 393399751.

157993393 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It can be written as a sum of positive squares in 2 ways, for example, as 55234624 + 102758769 = 7432^2 + 10137^2 .

It is a cyclic number.

It is not a de Polignac number, because 157993393 - 2¹⁷ = 157862321 is a prime.

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (157993397) 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, 4646848 + ... + 4646881.

It is an arithmetic number, because the mean of its divisors is an integer number (41821785).

Almost surely, 2^157993393 is an apocalyptic number.

It is an amenable number.

157993393 is a deficient number, since it is larger than the sum of its proper divisors (9293747).

157993393 is an equidigital number, since it uses as much as digits as its factorization.

157993393 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9293746.

The product of its digits is 688905, while the sum is 49.

The square root of 157993393 is about 12569.5422748802. The cubic root of 157993393 is about 540.6044819772.

The spelling of 157993393 in words is "one hundred fifty-seven million, nine hundred ninety-three thousand, three hundred ninety-three".