1401390639 has 40 divisors (see below), whose sum is σ = 2287655040. Its totient is φ = 847875600.

The previous prime is 1401390589. The next prime is 1401390671. The reversal of 1401390639 is 9360931041.

1401390639 is a `hidden beast` number, since 1 + 4 + 0 + 13 + 9 + 0 + 639 = 666.

1401390639 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is a de Polignac number, because none of the positive numbers 2^k-1401390639 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1401390689) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 764454 + ... + 766284.

It is an arithmetic number, because the mean of its divisors is an integer number (57191376).

Almost surely, 2^1401390639 is an apocalyptic number.

1401390639 is a deficient number, since it is larger than the sum of its proper divisors (886264401).

1401390639 is a wasteful number, since it uses less digits than its factorization.

1401390639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2713 (or 2704 counting only the distinct ones).

The product of its (nonzero) digits is 17496, while the sum is 36.

The square root of 1401390639 is about 37435.1524506045. The cubic root of 1401390639 is about 1119.0592224764.

The spelling of 1401390639 in words is "one billion, four hundred one million, three hundred ninety thousand, six hundred thirty-nine".