12691945 has 32 divisors (see below), whose sum is σ = 18724608. Its totient is φ = 8060928.

The previous prime is 12691933. The next prime is 12691957. The reversal of 12691945 is 54919621.

12691945 is digitally balanced in base 2 and base 8, because in such bases it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (12691933) and next prime (12691957).

It is a cyclic number.

It is not a de Polignac number, because 12691945 - 2²³ = 4303337 is a prime.

It is a super-2 number, since 2×12691945² = 322170935766050, which contains 22 as substring.

12691945 is strictly pandigital in base 8.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 49257 + ... + 49513.

It is an arithmetic number, because the mean of its divisors is an integer number (585144).

Almost surely, 2^12691945 is an apocalyptic number.

It is an amenable number.

12691945 is a deficient number, since it is larger than the sum of its proper divisors (6032663).

12691945 is a wasteful number, since it uses less digits than its factorization.

12691945 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 369.

The product of its digits is 19440, while the sum is 37.

The square root of 12691945 is about 3562.5756132327. The cubic root of 12691945 is about 233.2613190462.

The spelling of 12691945 in words is "twelve million, six hundred ninety-one thousand, nine hundred forty-five".