1257680813 has 8 divisors (see below), whose sum is σ = 1354663200. Its totient is φ = 1163777328.

The previous prime is 1257680803. The next prime is 1257680821. The reversal of 1257680813 is 3180867521.

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 1257680813 - 2⁴ = 1257680797 is a prime.

It is a super-2 number, since 2×1257680813² = 3163522054776681938, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1257680803) 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, 768878 + ... + 770511.

It is an arithmetic number, because the mean of its divisors is an integer number (169332900).

Almost surely, 2^1257680813 is an apocalyptic number.

It is an amenable number.

1257680813 is a deficient number, since it is larger than the sum of its proper divisors (96982387).

1257680813 is a wasteful number, since it uses less digits than its factorization.

1257680813 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1539451.

The product of its (nonzero) digits is 80640, while the sum is 41.

The square root of 1257680813 is about 35463.7958064277. The cubic root of 1257680813 is about 1079.4192159096.

The spelling of 1257680813 in words is "one billion, two hundred fifty-seven million, six hundred eighty thousand, eight hundred thirteen".