21001010102122 has 4 divisors (see below), whose sum is σ = 31501515153186. Its totient is φ = 10500505051060.

The previous prime is 21001010102101. The next prime is 21001010102129. The reversal of 21001010102122 is 22120101010012.

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

It can be written as a sum of positive squares in only one way, i.e., 14207162639121 + 6793847463001 = 3769239^2 + 2606501^2 .

It is not an unprimeable number, because it can be changed into a prime (21001010102129) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5250252525529 + ... + 5250252525532.

Almost surely, 2^{21001010102122} is an apocalyptic number.

21001010102122 is a deficient number, since it is larger than the sum of its proper divisors (10500505051064).

21001010102122 is a wasteful number, since it uses less digits than its factorization.

21001010102122 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10500505051063.

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 21001010102122 its reverse (22120101010012), we get a palindrome (43121111112134).

The spelling of 21001010102122 in words is "twenty-one trillion, one billion, ten million, one hundred two thousand, one hundred twenty-two".