1240391880 has 480 divisors, whose sum is σ = 5231512440. Its totient is φ = 261273600.

The previous prime is 1240391861. The next prime is 1240391881. The reversal of 1240391880 is 881930421.

It can be written as a sum of positive squares in 4 ways, for example, as 984327876 + 256064004 = 31374^2 + 16002^2 .

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

It is not an unprimeable number, because it can be changed into a prime (1240391881) by changing a digit.

It is a polite number, since it can be written in 119 ways as a sum of consecutive naturals, for example, 2063580 + ... + 2064180.

Almost surely, 2^1240391880 is an apocalyptic number.

1240391880 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 1240391880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2615756220).

1240391880 is an abundant number, since it is smaller than the sum of its proper divisors (3991120560).

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

1240391880 is a wasteful number, since it uses less digits than its factorization.

1240391880 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 651 (or 631 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 36.

The square root of 1240391880 is about 35219.1976058513. The cubic root of 1240391880 is about 1074.4502341256.

The spelling of 1240391880 in words is "one billion, two hundred forty million, three hundred ninety-one thousand, eight hundred eighty".