1257095680 has 80 divisors (see below), whose sum is σ = 3031852824. Its totient is φ = 499875840.

The previous prime is 1257095647. The next prime is 1257095681. The reversal of 1257095680 is 865907521.

It can be written as a sum of positive squares in 4 ways, for example, as 1000583424 + 256512256 = 31632^2 + 16016^2 .

It is a tau number, because it is divible by the number of its divisors (80).

It is not an unprimeable number, because it can be changed into a prime (1257095681) 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, 462004 + ... + 464716.

Almost surely, 2^1257095680 is an apocalyptic number.

1257095680 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1257095680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1515926412).

1257095680 is an abundant number, since it is smaller than the sum of its proper divisors (1774757144).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1257095680 is an equidigital number, since it uses as much as digits as its factorization.

1257095680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2917 (or 2901 counting only the distinct ones).

The product of its (nonzero) digits is 151200, while the sum is 43.

The square root of 1257095680 is about 35455.5451234359. The cubic root of 1257095680 is about 1079.2517908699.

The spelling of 1257095680 in words is "one billion, two hundred fifty-seven million, ninety-five thousand, six hundred eighty".