12155121947 has 2 divisors, whose sum is σ = 12155121948. Its totient is φ = 12155121946.

The previous prime is 12155121931. The next prime is 12155122061. The reversal of 12155121947 is 74912155121.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 12155121947 - 2⁴ = 12155121931 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 12155121947.

It is not a weakly prime, because it can be changed into another prime (12155121547) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6077560973 + 6077560974.

It is an arithmetic number, because the mean of its divisors is an integer number (6077560974).

Almost surely, 2^12155121947 is an apocalyptic number.

12155121947 is a deficient number, since it is larger than the sum of its proper divisors (1).

12155121947 is an equidigital number, since it uses as much as digits as its factorization.

12155121947 is an evil number, because the sum of its binary digits is even.

The product of its digits is 25200, while the sum is 38.

The spelling of 12155121947 in words is "twelve billion, one hundred fifty-five million, one hundred twenty-one thousand, nine hundred forty-seven".