157240681 has 8 divisors (see below), whose sum is σ = 170416904. Its totient is φ = 144218880.

The previous prime is 157240597. The next prime is 157240693. The reversal of 157240681 is 186042751.

It can be written as a sum of positive squares in 4 ways, for example, as 10830681 + 146410000 = 3291^2 + 12100^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 157240681 - 2¹³ = 157232489 is a prime.

It is a super-2 number, since 2×157240681² = 49449263522687522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (157240481) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 36480 + ... + 40561.

It is an arithmetic number, because the mean of its divisors is an integer number (21302113).

Almost surely, 2^157240681 is an apocalyptic number.

It is an amenable number.

157240681 is a deficient number, since it is larger than the sum of its proper divisors (13176223).

157240681 is a wasteful number, since it uses less digits than its factorization.

157240681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 77211.

The product of its (nonzero) digits is 13440, while the sum is 34.

The square root of 157240681 is about 12539.5646256160. The cubic root of 157240681 is about 539.7445991595.

The spelling of 157240681 in words is "one hundred fifty-seven million, two hundred forty thousand, six hundred eighty-one".