102111001020 has 432 divisors, whose sum is σ = 385172843328. Its totient is φ = 21778606080.

The previous prime is 102111000991. The next prime is 102111001021. The reversal of 102111001020 is 20100111201.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a junction number, because it is equal to n+sod(n) for n = 102111000993 and 102111001011.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (102111001021) by changing a digit.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 8311122 + ... + 8323398.

It is an arithmetic number, because the mean of its divisors is an integer number (891603804).

Almost surely, 2^102111001020 is an apocalyptic number.

102111001020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 102111001020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (192586421664).

102111001020 is an abundant number, since it is smaller than the sum of its proper divisors (283061842308).

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

102111001020 is a wasteful number, since it uses less digits than its factorization.

102111001020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12370 (or 12358 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 9.

Adding to 102111001020 its reverse (20100111201), we get a palindrome (122211112221).

The spelling of 102111001020 in words is "one hundred two billion, one hundred eleven million, one thousand, twenty".