2001212123 has 4 divisors (see below), whose sum is σ = 2003037480. Its totient is φ = 1999386768.

The previous prime is 2001212117. The next prime is 2001212149. The reversal of 2001212123 is 3212121002.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 2001212123 - 2⁸ = 2001211867 is a prime.

It is a super-2 number, since 2×2001212123² = 8009699922484334258, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2001212098 and 2001212107.

It is not an unprimeable number, because it can be changed into a prime (2001212153) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 911033 + ... + 913226.

It is an arithmetic number, because the mean of its divisors is an integer number (500759370).

Almost surely, 2^2001212123 is an apocalyptic number.

2001212123 is a deficient number, since it is larger than the sum of its proper divisors (1825357).

2001212123 is a wasteful number, since it uses less digits than its factorization.

2001212123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1825356.

The product of its (nonzero) digits is 48, while the sum is 14.

The square root of 2001212123 is about 44734.9094444149. The cubic root of 2001212123 is about 1260.1755283724.

Adding to 2001212123 its reverse (3212121002), we get a palindrome (5213333125).

The spelling of 2001212123 in words is "two billion, one million, two hundred twelve thousand, one hundred twenty-three".