1256722740 has 288 divisors, whose sum is σ = 4760560896. Its totient is φ = 261273600.

The previous prime is 1256722729. The next prime is 1256722741. The reversal of 1256722740 is 472276521.

It is a happy number.

1256722740 is a `hidden beast` number, since 1 + 2 + 567 + 22 + 74 + 0 = 666.

1256722740 is digitally balanced in base 6, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 1256722695 and 1256722704.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1256722741) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 1195215 + ... + 1196265.

Almost surely, 2^1256722740 is an apocalyptic number.

1256722740 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 1256722740, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2380280448).

1256722740 is an abundant number, since it is smaller than the sum of its proper divisors (3503838156).

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

1256722740 is a wasteful number, since it uses less digits than its factorization.

1256722740 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1159 (or 1154 counting only the distinct ones).

The product of its (nonzero) digits is 47040, while the sum is 36.

The square root of 1256722740 is about 35450.2854713471. The cubic root of 1256722740 is about 1079.1450538415.

The spelling of 1256722740 in words is "one billion, two hundred fifty-six million, seven hundred twenty-two thousand, seven hundred forty".