1281394157 has 8 divisors (see below), whose sum is σ = 1291802400. Its totient is φ = 1271003184.

The previous prime is 1281394139. The next prime is 1281394199. The reversal of 1281394157 is 7514931821.

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

It is a cyclic number.

It is not a de Polignac number, because 1281394157 - 2⁸ = 1281393901 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1281394757) 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, 173894 + ... + 181112.

It is an arithmetic number, because the mean of its divisors is an integer number (161475300).

Almost surely, 2^1281394157 is an apocalyptic number.

It is an amenable number.

1281394157 is a deficient number, since it is larger than the sum of its proper divisors (10408243).

1281394157 is a wasteful number, since it uses less digits than its factorization.

1281394157 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8635.

The product of its digits is 60480, while the sum is 41.

The square root of 1281394157 is about 35796.5662738760. The cubic root of 1281394157 is about 1086.1611040555.

The spelling of 1281394157 in words is "one billion, two hundred eighty-one million, three hundred ninety-four thousand, one hundred fifty-seven".