1201110021 has 24 divisors (see below), whose sum is σ = 1793702144. Its totient is φ = 773906400.

The previous prime is 1201110007. The next prime is 1201110037. The reversal of 1201110021 is 1200111021.

It is a happy number.

It is not a de Polignac number, because 1201110021 - 2¹³ = 1201101829 is a prime.

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

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1201109985 and 1201110012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1201110041) 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, 38340 + ... + 62226.

Almost surely, 2^1201110021 is an apocalyptic number.

It is an amenable number.

1201110021 is a deficient number, since it is larger than the sum of its proper divisors (592592123).

1201110021 is a wasteful number, since it uses less digits than its factorization.

1201110021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24081 (or 24078 counting only the distinct ones).

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

The square root of 1201110021 is about 34657.0342210640. The cubic root of 1201110021 is about 1062.9861274620.

Adding to 1201110021 its reverse (1200111021), we get a palindrome (2401221042).

The spelling of 1201110021 in words is "one billion, two hundred one million, one hundred ten thousand, twenty-one".