1257081331 has 8 divisors (see below), whose sum is σ = 1371626928. Its totient is φ = 1142580000.

The previous prime is 1257081313. The next prime is 1257081347. The reversal of 1257081331 is 1331807521.

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 1257081331 - 2²¹ = 1254984179 is a prime.

It is a super-2 number, since 2×1257081331² = 3160506945497463122, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1257081293 and 1257081302.

It is not an unprimeable number, because it can be changed into a prime (1257081391) 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, 83481 + ... + 97381.

It is an arithmetic number, because the mean of its divisors is an integer number (171453366).

Almost surely, 2^1257081331 is an apocalyptic number.

1257081331 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

1257081331 is a deficient number, since it is larger than the sum of its proper divisors (114545597).

1257081331 is a wasteful number, since it uses less digits than its factorization.

1257081331 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22133.

The product of its (nonzero) digits is 5040, while the sum is 31.

The square root of 1257081331 is about 35455.3427708716. The cubic root of 1257081331 is about 1079.2476845151.

Adding to 1257081331 its reverse (1331807521), we get a palindrome (2588888852).

The spelling of 1257081331 in words is "one billion, two hundred fifty-seven million, eighty-one thousand, three hundred thirty-one".