1257901361 has 18 divisors (see below), whose sum is σ = 1341571686. Its totient is φ = 1178699200.

The previous prime is 1257901343. The next prime is 1257901399. The reversal of 1257901361 is 1631097521.

It can be written as a sum of positive squares in 3 ways, for example, as 22800625 + 1235100736 = 4775^2 + 35144^2 .

It is not a de Polignac number, because 1257901361 - 2²² = 1253707057 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 (1257901301) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 6585776 + ... + 6585966.

Almost surely, 2^1257901361 is an apocalyptic number.

It is an amenable number.

1257901361 is a deficient number, since it is larger than the sum of its proper divisors (83670325).

1257901361 is an frugal number, since it uses more digits than its factorization.

1257901361 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 481 (or 261 counting only the distinct ones).

The product of its (nonzero) digits is 11340, while the sum is 35.

The square root of 1257901361 is about 35466.9051511405. The cubic root of 1257901361 is about 1079.4823081856.

Adding to 1257901361 its reverse (1631097521), we get a palindrome (2888998882).

The spelling of 1257901361 in words is "one billion, two hundred fifty-seven million, nine hundred one thousand, three hundred sixty-one".