12251491909781 has 8 divisors (see below), whose sum is σ = 12972639447360. Its totient is φ = 11530396765888.

The previous prime is 12251491909753. The next prime is 12251491909793. The reversal of 12251491909781 is 18790919415221.

It is a happy number.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-12251491909781 is a prime.

It is a super-2 number, since 2×12251491909781² (a number of 27 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 12251491909781.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12251491902781) 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, 12616481 + ... + 13552806.

It is an arithmetic number, because the mean of its divisors is an integer number (1621579930920).

Almost surely, 2^{12251491909781} is an apocalyptic number.

It is an amenable number.

12251491909781 is a deficient number, since it is larger than the sum of its proper divisors (721147537579).

12251491909781 is a wasteful number, since it uses less digits than its factorization.

12251491909781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26196843.

The product of its (nonzero) digits is 3265920, while the sum is 59.

The spelling of 12251491909781 in words is "twelve trillion, two hundred fifty-one billion, four hundred ninety-one million, nine hundred nine thousand, seven hundred eighty-one".