1258840440 has 720 divisors, whose sum is σ = 5301034200. Its totient is φ = 266872320.

The previous prime is 1258840417. The next prime is 1258840447. The reversal of 1258840440 is 440488521.

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 = 1258840395 and 1258840404.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1258840447) by changing a digit.

It is a polite number, since it can be written in 179 ways as a sum of consecutive naturals, for example, 66254751 + ... + 66254769.

Almost surely, 2^1258840440 is an apocalyptic number.

1258840440 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 1258840440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2650517100).

1258840440 is an abundant number, since it is smaller than the sum of its proper divisors (4042193760).

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

1258840440 is a wasteful number, since it uses less digits than its factorization.

1258840440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 90 (or 53 counting only the distinct ones).

The product of its (nonzero) digits is 40960, while the sum is 36.

The square root of 1258840440 is about 35480.1414878802. The cubic root of 1258840440 is about 1079.7508684613.

The spelling of 1258840440 in words is "one billion, two hundred fifty-eight million, eight hundred forty thousand, four hundred forty".