1399945680 has 300 divisors, whose sum is σ = 5657333220. Its totient is φ = 319915008.

The previous prime is 1399945667. The next prime is 1399945693. The reversal of 1399945680 is 865499931.

It is an interprime number because it is at equal distance from previous prime (1399945667) and next prime (1399945693).

It can be written as a sum of positive squares in 2 ways, for example, as 276623424 + 1123322256 = 16632^2 + 33516^2 .

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 59 ways as a sum of consecutive naturals, for example, 315316 + ... + 319724.

Almost surely, 2^1399945680 is an apocalyptic number.

1399945680 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 1399945680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2828666610).

1399945680 is an abundant number, since it is smaller than the sum of its proper divisors (4257387540).

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

1399945680 is a wasteful number, since it uses less digits than its factorization.

1399945680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4448 (or 4426 counting only the distinct ones).

The product of its (nonzero) digits is 2099520, while the sum is 54.

The square root of 1399945680 is about 37415.8479791652. The cubic root of 1399945680 is about 1118.6744735173.

The spelling of 1399945680 in words is "one billion, three hundred ninety-nine million, nine hundred forty-five thousand, six hundred eighty".