157812493 has 4 divisors (see below), whose sum is σ = 157873788. Its totient is φ = 157751200.

The previous prime is 157812467. The next prime is 157812509. The reversal of 157812493 is 394218751.

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 65901924 + 91910569 = 8118^2 + 9587^2 .

It is a cyclic number.

It is not a de Polignac number, because 157812493 - 2⁹ = 157811981 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (157812293) 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, 26608 + ... + 31993.

It is an arithmetic number, because the mean of its divisors is an integer number (39468447).

Almost surely, 2^157812493 is an apocalyptic number.

It is an amenable number.

157812493 is a deficient number, since it is larger than the sum of its proper divisors (61295).

157812493 is an equidigital number, since it uses as much as digits as its factorization.

157812493 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 61294.

The product of its digits is 60480, while the sum is 40.

The square root of 157812493 is about 12562.3442477907. The cubic root of 157812493 is about 540.3980752462.

The spelling of 157812493 in words is "one hundred fifty-seven million, eight hundred twelve thousand, four hundred ninety-three".