13721990 has 16 divisors (see below), whose sum is σ = 25999920. Its totient is φ = 5199840.

The previous prime is 13721987. The next prime is 13721993. The reversal of 13721990 is 9912731.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (13721987) and next prime (13721993).

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13721993) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 35921 + ... + 36300.

It is an arithmetic number, because the mean of its divisors is an integer number (1624995).

Almost surely, 2^13721990 is an apocalyptic number.

13721990 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

13721990 is a deficient number, since it is larger than the sum of its proper divisors (12277930).

13721990 is a wasteful number, since it uses less digits than its factorization.

13721990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 72247.

The product of its (nonzero) digits is 3402, while the sum is 32.

The square root of 13721990 is about 3704.3204505010. The cubic root of 13721990 is about 239.4082063022.

The spelling of 13721990 in words is "thirteen million, seven hundred twenty-one thousand, nine hundred ninety".