1256920240 has 40 divisors (see below), whose sum is σ = 2926093968. Its totient is φ = 502122240.

The previous prime is 1256920219. The next prime is 1256920267. The reversal of 1256920240 is 420296521.

It is a tau number, because it is divible by the number of its divisors (40).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 55194 + ... + 74566.

Almost surely, 2^1256920240 is an apocalyptic number.

1256920240 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1256920240 is an abundant number, since it is smaller than the sum of its proper divisors (1669173728).

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

1256920240 is a wasteful number, since it uses less digits than its factorization.

1256920240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20197 (or 20191 counting only the distinct ones).

The product of its (nonzero) digits is 8640, while the sum is 31.

The square root of 1256920240 is about 35453.0709530218. The cubic root of 1256920240 is about 1079.2015818190.

The spelling of 1256920240 in words is "one billion, two hundred fifty-six million, nine hundred twenty thousand, two hundred forty".