157457781 has 24 divisors (see below), whose sum is σ = 245392056. Its totient is φ = 96716160.

The previous prime is 157457771. The next prime is 157457813. The reversal of 157457781 is 187754751.

157457781 is a `hidden beast` number, since 1 + 5 + 74 + 577 + 8 + 1 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 28998225 + 128459556 = 5385^2 + 11334^2 .

It is not a de Polignac number, because 157457781 - 2¹⁴ = 157441397 is a prime.

It is a super-2 number, since 2×157457781² = 49585905594887922, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (157457771) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 89571 + ... + 91311.

It is an arithmetic number, because the mean of its divisors is an integer number (10224669).

Almost surely, 2^157457781 is an apocalyptic number.

It is an amenable number.

157457781 is a deficient number, since it is larger than the sum of its proper divisors (87934275).

157457781 is a wasteful number, since it uses less digits than its factorization.

157457781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2533 (or 2530 counting only the distinct ones).

The product of its digits is 274400, while the sum is 45.

The square root of 157457781 is about 12548.2182400530. The cubic root of 157457781 is about 539.9928908529.

The spelling of 157457781 in words is "one hundred fifty-seven million, four hundred fifty-seven thousand, seven hundred eighty-one".