121256828115 has 128 divisors (see below), whose sum is σ = 222299043840. Its totient is φ = 56072282112.

The previous prime is 121256828113. The next prime is 121256828129. The reversal of 121256828115 is 511828652121.

It is a happy number.

It is not a de Polignac number, because 121256828115 - 2¹ = 121256828113 is a prime.

It is not an unprimeable number, because it can be changed into a prime (121256828113) by changing a digit.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 104261524 + ... + 104262686.

It is an arithmetic number, because the mean of its divisors is an integer number (1736711280).

Almost surely, 2^121256828115 is an apocalyptic number.

121256828115 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

121256828115 is a deficient number, since it is larger than the sum of its proper divisors (101042215725).

121256828115 is a wasteful number, since it uses less digits than its factorization.

121256828115 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1853.

The product of its digits is 76800, while the sum is 42.

The spelling of 121256828115 in words is "one hundred twenty-one billion, two hundred fifty-six million, eight hundred twenty-eight thousand, one hundred fifteen".