87121838939 has 2 divisors, whose sum is σ = 87121838940. Its totient is φ = 87121838938.

The previous prime is 87121838929. The next prime is 87121839011. The reversal of 87121838939 is 93983812178.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 87121838939 - 2³² = 82826871643 is a prime.

It is a super-2 number, since 2×87121838939² (a number of 23 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (87121838929) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 43560919469 + 43560919470.

It is an arithmetic number, because the mean of its divisors is an integer number (43560919470).

Almost surely, 2^87121838939 is an apocalyptic number.

87121838939 is a deficient number, since it is larger than the sum of its proper divisors (1).

87121838939 is an equidigital number, since it uses as much as digits as its factorization.

87121838939 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5225472, while the sum is 59.

The spelling of 87121838939 in words is "eighty-seven billion, one hundred twenty-one million, eight hundred thirty-eight thousand, nine hundred thirty-nine".