1000111200021 has 24 divisors (see below), whose sum is σ = 1483960359960. Its totient is φ = 648584395776.

The previous prime is 1000111200017. The next prime is 1000111200089. The reversal of 1000111200021 is 1200021110001.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 702528948900 + 297582251121 = 838170^2 + 545511^2 .

It is not a de Polignac number, because 1000111200021 - 2² = 1000111200017 is a prime.

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 = 1000111199976 and 1000111200012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1000111200091) 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, 1282765 + ... + 1909373.

It is an arithmetic number, because the mean of its divisors is an integer number (61831681665).

Almost surely, 2^{1000111200021} is an apocalyptic number.

It is an amenable number.

1000111200021 is a deficient number, since it is larger than the sum of its proper divisors (483849159939).

1000111200021 is a wasteful number, since it uses less digits than its factorization.

1000111200021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 631445 (or 631442 counting only the distinct ones).

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

Adding to 1000111200021 its reverse (1200021110001), we get a palindrome (2200132310022).

The spelling of 1000111200021 in words is "one trillion, one hundred eleven million, two hundred thousand, twenty-one".