157628381 has 2 divisors, whose sum is σ = 157628382. Its totient is φ = 157628380.

The previous prime is 157628327. The next prime is 157628417. The reversal of 157628381 is 183826751.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 144240100 + 13388281 = 12010^2 + 3659^2 .

It is an emirp because it is prime and its reverse (183826751) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-157628381 is a prime.

It is a super-2 number, since 2×157628381² = 49693412993362322, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (157628321) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 78814190 + 78814191.

It is an arithmetic number, because the mean of its divisors is an integer number (78814191).

Almost surely, 2^157628381 is an apocalyptic number.

It is an amenable number.

157628381 is a deficient number, since it is larger than the sum of its proper divisors (1).

157628381 is an equidigital number, since it uses as much as digits as its factorization.

157628381 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 80640, while the sum is 41.

The square root of 157628381 is about 12555.0141776105. The cubic root of 157628381 is about 540.1878416010.

The spelling of 157628381 in words is "one hundred fifty-seven million, six hundred twenty-eight thousand, three hundred eighty-one".