10202121111978 has 12 divisors (see below), whose sum is σ = 22104595742658. Its totient is φ = 3400707037320.

The previous prime is 10202121111977. The next prime is 10202121111979. The reversal of 10202121111978 is 87911112120201.

10202121111978 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (10202121111977) and next prime (10202121111979).

It can be written as a sum of positive squares in only one way, i.e., 9478867815729 + 723253296249 = 3078777^2 + 850443^2 .

It is not an unprimeable number, because it can be changed into a prime (10202121111977) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 283392253093 + ... + 283392253128.

Almost surely, 2^{10202121111978} is an apocalyptic number.

10202121111978 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

10202121111978 is an abundant number, since it is smaller than the sum of its proper divisors (11902474630680).

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

10202121111978 is a wasteful number, since it uses less digits than its factorization.

10202121111978 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 566784506229 (or 566784506226 counting only the distinct ones).

The product of its (nonzero) digits is 4032, while the sum is 36.

The spelling of 10202121111978 in words is "ten trillion, two hundred two billion, one hundred twenty-one million, one hundred eleven thousand, nine hundred seventy-eight".