1399861440 has 280 divisors, whose sum is σ = 5078486160. Its totient is φ = 365893632.

The previous prime is 1399861439. The next prime is 1399861457. The reversal of 1399861440 is 441689931.

It is a super-2 number, since 2×1399861440² = 3919224102397747200, which contains 22 as substring.

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 1373251 + ... + 1374269.

Almost surely, 2^1399861440 is an apocalyptic number.

1399861440 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 1399861440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2539243080).

1399861440 is an abundant number, since it is smaller than the sum of its proper divisors (3678624720).

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

1399861440 is a wasteful number, since it uses less digits than its factorization.

1399861440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1101 (or 1082 counting only the distinct ones).

The product of its (nonzero) digits is 186624, while the sum is 45.

The square root of 1399861440 is about 37414.7222360397. The cubic root of 1399861440 is about 1118.6520347829.

It can be divided in two parts, 1399861 and 440, that added together give a triangular number (1400301 = T₁₆₇₃).

The spelling of 1399861440 in words is "one billion, three hundred ninety-nine million, eight hundred sixty-one thousand, four hundred forty".