12381722537 has 4 divisors (see below), whose sum is σ = 12381966480. Its totient is φ = 12381478596.

The previous prime is 12381722497. The next prime is 12381722539. The reversal of 12381722537 is 73522718321.

It is a happy number.

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 not a de Polignac number, because 12381722537 - 2¹⁸ = 12381460393 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 12381722494 and 12381722503.

It is not an unprimeable number, because it can be changed into a prime (12381722539) 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, 13943 + ... + 157980.

It is an arithmetic number, because the mean of its divisors is an integer number (3095491620).

Almost surely, 2^12381722537 is an apocalyptic number.

It is an amenable number.

12381722537 is a deficient number, since it is larger than the sum of its proper divisors (243943).

12381722537 is an equidigital number, since it uses as much as digits as its factorization.

12381722537 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 243942.

The product of its digits is 141120, while the sum is 41.

The spelling of 12381722537 in words is "twelve billion, three hundred eighty-one million, seven hundred twenty-two thousand, five hundred thirty-seven".