26139561 has 8 divisors (see below), whose sum is σ = 39831744. Its totient is φ = 14936880.

The previous prime is 26139559. The next prime is 26139563. The reversal of 26139561 is 16593162.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (26139559) and next prime (26139563).

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

It is not a de Polignac number, because 26139561 - 2¹ = 26139559 is a prime.

It is a Smith number, since the sum of its digits (33) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (26139563) 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, 622350 + ... + 622391.

It is an arithmetic number, because the mean of its divisors is an integer number (4978968).

Almost surely, 2^26139561 is an apocalyptic number.

26139561 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

26139561 is a deficient number, since it is larger than the sum of its proper divisors (13692183).

26139561 is a wasteful number, since it uses less digits than its factorization.

26139561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1244751.

The product of its digits is 9720, while the sum is 33.

The square root of 26139561 is about 5112.6862802249. The cubic root of 26139561 is about 296.7787239576.

The spelling of 26139561 in words is "twenty-six million, one hundred thirty-nine thousand, five hundred sixty-one".