1200110001021 has 24 divisors (see below), whose sum is σ = 1782646908120. Its totient is φ = 777442513536.

The previous prime is 1200110001011. The next prime is 1200110001047. The reversal of 1200110001021 is 1201000110021.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 43990448121 + 1156119552900 = 209739^2 + 1075230^2 .

It is not a de Polignac number, because 1200110001021 - 2¹⁰ = 1200109999997 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 = 1200110000994 and 1200110001012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1200110001011) 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, 2073726 + ... + 2588543.

It is an arithmetic number, because the mean of its divisors is an integer number (74276954505).

Almost surely, 2^{1200110001021} is an apocalyptic number.

It is an amenable number.

1200110001021 is a deficient number, since it is larger than the sum of its proper divisors (582536907099).

1200110001021 is a wasteful number, since it uses less digits than its factorization.

1200110001021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4663085 (or 4663082 counting only the distinct ones).

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

Adding to 1200110001021 its reverse (1201000110021), we get a palindrome (2401110111042).

The spelling of 1200110001021 in words is "one trillion, two hundred billion, one hundred ten million, one thousand, twenty-one".