1398779520 has 256 divisors, whose sum is σ = 4681359360. Its totient is φ = 354816000.

The previous prime is 1398779519. The next prime is 1398779521. The reversal of 1398779520 is 259778931.

1398779520 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (1398779519) and next prime (1398779521).

It is not an unprimeable number, because it can be changed into a prime (1398779521) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 4225755 + ... + 4226085.

It is an arithmetic number, because the mean of its divisors is an integer number (18286560).

Almost surely, 2^1398779520 is an apocalyptic number.

1398779520 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 1398779520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2340679680).

1398779520 is an abundant number, since it is smaller than the sum of its proper divisors (3282579840).

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

1398779520 is a wasteful number, since it uses less digits than its factorization.

1398779520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 455 (or 443 counting only the distinct ones).

The product of its (nonzero) digits is 952560, while the sum is 51.

The square root of 1398779520 is about 37400.2609616564. The cubic root of 1398779520 is about 1118.3637672180.

The spelling of 1398779520 in words is "one billion, three hundred ninety-eight million, seven hundred seventy-nine thousand, five hundred twenty".