1399686642 has 80 divisors (see below), whose sum is σ = 3408134400. Its totient is φ = 427718880.

The previous prime is 1399686641. The next prime is 1399686671. The reversal of 1399686642 is 2466869931.

It is a Smith number, since the sum of its digits (54) coincides with the sum of the digits of its prime factors.

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

It is not an unprimeable number, because it can be changed into a prime (1399686641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 88084 + ... + 102752.

It is an arithmetic number, because the mean of its divisors is an integer number (42601680).

Almost surely, 2^1399686642 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1399686642, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1704067200).

1399686642 is an abundant number, since it is smaller than the sum of its proper divisors (2008447758).

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

1399686642 is a wasteful number, since it uses less digits than its factorization.

1399686642 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14733 (or 14724 counting only the distinct ones).

The product of its digits is 3359232, while the sum is 54.

The square root of 1399686642 is about 37412.3862109863. The cubic root of 1399686642 is about 1118.6054715369.

The spelling of 1399686642 in words is "one billion, three hundred ninety-nine million, six hundred eighty-six thousand, six hundred forty-two".