10121531778 has 48 divisors (see below), whose sum is σ = 22356655776. Its totient is φ = 3308798400.

The previous prime is 10121531747. The next prime is 10121531779. The reversal of 10121531778 is 87713512101.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (10121531779) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 179953 + ... + 229403.

It is an arithmetic number, because the mean of its divisors is an integer number (465763662).

Almost surely, 2^10121531778 is an apocalyptic number.

10121531778 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

10121531778 is an abundant number, since it is smaller than the sum of its proper divisors (12235123998).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

10121531778 is a wasteful number, since it uses less digits than its factorization.

10121531778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 49679 (or 49676 counting only the distinct ones).

The product of its (nonzero) digits is 11760, while the sum is 36.

The spelling of 10121531778 in words is "ten billion, one hundred twenty-one million, five hundred thirty-one thousand, seven hundred seventy-eight".