1520778240 has 440 divisors, whose sum is σ = 5766153360. Its totient is φ = 382205952.

The previous prime is 1520778151. The next prime is 1520778247. The reversal of 1520778240 is 428770251.

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 = 1520778195 and 1520778204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1520778247) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 7879584 + ... + 7879776.

It is an arithmetic number, because the mean of its divisors is an integer number (13104894).

Almost surely, 2^1520778240 is an apocalyptic number.

1520778240 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 1520778240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2883076680).

1520778240 is an abundant number, since it is smaller than the sum of its proper divisors (4245375120).

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

1520778240 is a wasteful number, since it uses less digits than its factorization.

1520778240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 249 (or 222 counting only the distinct ones).

The product of its (nonzero) digits is 31360, while the sum is 36.

The square root of 1520778240 is about 38997.1568194401. The cubic root of 1520778240 is about 1149.9756113290.

The spelling of 1520778240 in words is "one billion, five hundred twenty million, seven hundred seventy-eight thousand, two hundred forty".