201201000021 has 12 divisors (see below), whose sum is σ = 332141333472. Its totient is φ = 114971999976.

The previous prime is 201201000017. The next prime is 201201000037. The reversal of 201201000021 is 120000102102.

It is not a de Polignac number, because 201201000021 - 2² = 201201000017 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 = 201200999967 and 201201000012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (201201000421) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1596833271 + ... + 1596833396.

It is an arithmetic number, because the mean of its divisors is an integer number (27678444456).

Almost surely, 2^201201000021 is an apocalyptic number.

201201000021 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

201201000021 is a deficient number, since it is larger than the sum of its proper divisors (130940333451).

201201000021 is a wasteful number, since it uses less digits than its factorization.

201201000021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3193666680 (or 3193666677 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 9.

Adding to 201201000021 its reverse (120000102102), we get a palindrome (321201102123).

The spelling of 201201000021 in words is "two hundred one billion, two hundred one million, twenty-one", and thus it is an aban number.