10200001221 has 10 divisors (see below), whose sum is σ = 15237038982. Its totient is φ = 6800000760.

The previous prime is 10200001183. The next prime is 10200001247. The reversal of 10200001221 is 12210000201.

It can be written as a sum of positive squares in only one way, i.e., 8938757025 + 1261244196 = 94545^2 + 35514^2 .

It is not a de Polignac number, because 10200001221 - 2¹³ = 10199993029 is a prime.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (10200001261) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 62962890 + ... + 62963051.

Almost surely, 2^10200001221 is an apocalyptic number.

It is an amenable number.

10200001221 is a deficient number, since it is larger than the sum of its proper divisors (5037037761).

10200001221 is an equidigital number, since it uses as much as digits as its factorization.

10200001221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 125925953 (or 125925944 counting only the distinct ones).

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

Adding to 10200001221 its reverse (12210000201), we get a palindrome (22410001422).

The spelling of 10200001221 in words is "ten billion, two hundred million, one thousand, two hundred twenty-one".