1257666480 has 320 divisors, whose sum is σ = 4986347520. Its totient is φ = 285410304.

The previous prime is 1257666469. The next prime is 1257666481. The reversal of 1257666480 is 846667521.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (1257666481) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 3371574 + ... + 3371946.

It is an arithmetic number, because the mean of its divisors is an integer number (15582336).

Almost surely, 2^1257666480 is an apocalyptic number.

1257666480 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 1257666480, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2493173760).

1257666480 is an abundant number, since it is smaller than the sum of its proper divisors (3728681040).

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

1257666480 is a wasteful number, since it uses less digits than its factorization.

1257666480 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 625 (or 613 counting only the distinct ones).

The product of its (nonzero) digits is 483840, while the sum is 45.

The square root of 1257666480 is about 35463.5937265247. The cubic root of 1257666480 is about 1079.4151154060.

The spelling of 1257666480 in words is "one billion, two hundred fifty-seven million, six hundred sixty-six thousand, four hundred eighty".