13987990 has 32 divisors (see below), whose sum is σ = 26853120. Its totient is φ = 5230944.

The previous prime is 13987969. The next prime is 13987997. The reversal of 13987990 is 9978931.

13987990 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a self number, because there is not a number n which added to its sum of digits gives 13987990.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13987997) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 15327 + ... + 16213.

It is an arithmetic number, because the mean of its divisors is an integer number (839160).

Almost surely, 2^13987990 is an apocalyptic number.

13987990 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

13987990 is a deficient number, since it is larger than the sum of its proper divisors (12865130).

13987990 is a wasteful number, since it uses less digits than its factorization.

13987990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 996.

The product of its (nonzero) digits is 122472, while the sum is 46.

The square root of 13987990 is about 3740.0521386740. The cubic root of 13987990 is about 240.9452881088.

The spelling of 13987990 in words is "thirteen million, nine hundred eighty-seven thousand, nine hundred ninety".