13661690 has 40 divisors (see below), whose sum is σ = 28738260. Its totient is φ = 4675776.

The previous prime is 13661689. The next prime is 13661759. The reversal of 13661690 is 9616631.

It can be written as a sum of positive squares in 2 ways, for example, as 12794929 + 866761 = 3577^2 + 931^2 .

It is a super-2 number, since 2×13661690² = 373283547312200, which contains 22 as substring.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 23726 + ... + 24294.

Almost surely, 2^13661690 is an apocalyptic number.

13661690 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

13661690 is an abundant number, since it is smaller than the sum of its proper divisors (15076570).

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

13661690 is an frugal number, since it uses more digits than its factorization.

13661690 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 604 (or 583 counting only the distinct ones).

The product of its (nonzero) digits is 5832, while the sum is 32.

The square root of 13661690 is about 3696.1723444666. The cubic root of 13661690 is about 239.0570057119.

The spelling of 13661690 in words is "thirteen million, six hundred sixty-one thousand, six hundred ninety".