210122001 has 12 divisors (see below), whose sum is σ = 311713012. Its totient is φ = 136295136.

The previous prime is 210121981. The next prime is 210122021. The reversal of 210122001 is 100221012.

It is an interprime number because it is at equal distance from previous prime (210121981) and next prime (210122021).

It can be written as a sum of positive squares in 2 ways, for example, as 96059601 + 114062400 = 9801^2 + 10680^2 .

It is not a de Polignac number, because 210122001 - 2⁹ = 210121489 is a prime.

It is a super-3 number, since 3×210122001³ (a number of 26 digits) contains 333 as substring.

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

It is not an unprimeable number, because it can be changed into a prime (210122021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 315166 + ... + 315831.

Almost surely, 2^210122001 is an apocalyptic number.

It is an amenable number.

210122001 is a deficient number, since it is larger than the sum of its proper divisors (101591011).

210122001 is a wasteful number, since it uses less digits than its factorization.

210122001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 631040 (or 631037 counting only the distinct ones).

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

The square root of 210122001 is about 14495.5855694070. The cubic root of 210122001 is about 594.5072784569.

Adding to 210122001 its reverse (100221012), we get a palindrome (310343013).

The spelling of 210122001 in words is "two hundred ten million, one hundred twenty-two thousand, one".