26861521 has 4 divisors (see below), whose sum is σ = 26958772. Its totient is φ = 26764272.

The previous prime is 26861509. The next prime is 26861543. The reversal of 26861521 is 12516862.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 2250000 + 24611521 = 1500^2 + 4961^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-26861521 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (26861551) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 48210 + ... + 48763.

It is an arithmetic number, because the mean of its divisors is an integer number (6739693).

Almost surely, 2^26861521 is an apocalyptic number.

It is an amenable number.

26861521 is a deficient number, since it is larger than the sum of its proper divisors (97251).

26861521 is an equidigital number, since it uses as much as digits as its factorization.

26861521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 97250.

The product of its digits is 5760, while the sum is 31.

The square root of 26861521 is about 5182.8101450854. The cubic root of 26861521 is about 299.4862354704.

The spelling of 26861521 in words is "twenty-six million, eight hundred sixty-one thousand, five hundred twenty-one".