1399436280 has 384 divisors, whose sum is σ = 5186488320. Its totient is φ = 324311040.

The previous prime is 1399436263. The next prime is 1399436287. The reversal of 1399436280 is 826349931.

It is a happy number.

1399436280 is a `hidden beast` number, since 13 + 9 + 9 + 4 + 3 + 628 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1399436287) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 13586709 + ... + 13586811.

It is an arithmetic number, because the mean of its divisors is an integer number (13506480).

Almost surely, 2^1399436280 is an apocalyptic number.

1399436280 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 1399436280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2593244160).

1399436280 is an abundant number, since it is smaller than the sum of its proper divisors (3787052040).

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

1399436280 is a wasteful number, since it uses less digits than its factorization.

1399436280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 251 (or 244 counting only the distinct ones).

The product of its (nonzero) digits is 279936, while the sum is 45.

The square root of 1399436280 is about 37409.0400839155. The cubic root of 1399436280 is about 1118.5387725596.

The spelling of 1399436280 in words is "one billion, three hundred ninety-nine million, four hundred thirty-six thousand, two hundred eighty".