12891437 has 8 divisors (see below), whose sum is σ = 13936440. Its totient is φ = 11854080.

The previous prime is 12891433. The next prime is 12891449. The reversal of 12891437 is 73419821.

12891437 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 32041 + 12859396 = 179^2 + 3586^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 12891437 - 2² = 12891433 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 12891397 and 12891406.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12891433) 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, 1889 + ... + 5417.

It is an arithmetic number, because the mean of its divisors is an integer number (1742055).

Almost surely, 2^12891437 is an apocalyptic number.

It is an amenable number.

12891437 is a deficient number, since it is larger than the sum of its proper divisors (1045003).

12891437 is a wasteful number, since it uses less digits than its factorization.

12891437 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3823.

The product of its digits is 12096, while the sum is 35.

The square root of 12891437 is about 3590.4647331508. The cubic root of 12891437 is about 234.4771050702.

The spelling of 12891437 in words is "twelve million, eight hundred ninety-one thousand, four hundred thirty-seven".