12699905 has 4 divisors (see below), whose sum is σ = 15239892. Its totient is φ = 10159920.

The previous prime is 12699899. The next prime is 12699931. The reversal of 12699905 is 50999621.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 50999621 = 53 ⋅962257.

It can be written as a sum of positive squares in 2 ways, for example, as 9431041 + 3268864 = 3071^2 + 1808^2 .

It is not a de Polignac number, because 12699905 - 2¹⁴ = 12683521 is a prime.

It is a super-2 number, since 2×12699905² = 322575174018050, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1269986 + ... + 1269995.

It is an arithmetic number, because the mean of its divisors is an integer number (3809973).

Almost surely, 2^12699905 is an apocalyptic number.

It is an amenable number.

12699905 is a deficient number, since it is larger than the sum of its proper divisors (2539987).

12699905 is an equidigital number, since it uses as much as digits as its factorization.

12699905 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2539986.

The product of its (nonzero) digits is 43740, while the sum is 41.

The square root of 12699905 is about 3563.6926073948. The cubic root of 12699905 is about 233.3100736452.

The spelling of 12699905 in words is "twelve million, six hundred ninety-nine thousand, nine hundred five".