20101212105 has 32 divisors (see below), whose sum is σ = 35830287360. Its totient is φ = 9554737920.

The previous prime is 20101212083. The next prime is 20101212113. The reversal of 20101212105 is 50121210102.

It is not a de Polignac number, because 20101212105 - 2¹⁸ = 20100949961 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1771641 + ... + 1782950.

It is an arithmetic number, because the mean of its divisors is an integer number (1119696480).

Almost surely, 2^20101212105 is an apocalyptic number.

It is an amenable number.

20101212105 is a deficient number, since it is larger than the sum of its proper divisors (15729075255).

20101212105 is a wasteful number, since it uses less digits than its factorization.

20101212105 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3554641.

The product of its (nonzero) digits is 40, while the sum is 15.

Adding to 20101212105 its reverse (50121210102), we get a palindrome (70222422207).

The spelling of 20101212105 in words is "twenty billion, one hundred one million, two hundred twelve thousand, one hundred five".