26139251497 has 4 divisors (see below), whose sum is σ = 26141225616. Its totient is φ = 26137277380.

The previous prime is 26139251473. The next prime is 26139251549. The reversal of 26139251497 is 79415293162.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-26139251497 is a prime.

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 26139251497.

It is not an unprimeable number, because it can be changed into a prime (26139251797) 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, 967063 + ... + 993724.

It is an arithmetic number, because the mean of its divisors is an integer number (6535306404).

Almost surely, 2^26139251497 is an apocalyptic number.

It is an amenable number.

26139251497 is a deficient number, since it is larger than the sum of its proper divisors (1974119).

26139251497 is a wasteful number, since it uses less digits than its factorization.

26139251497 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1974118.

The product of its digits is 816480, while the sum is 49.

The spelling of 26139251497 in words is "twenty-six billion, one hundred thirty-nine million, two hundred fifty-one thousand, four hundred ninety-seven".