21100002122 has 4 divisors (see below), whose sum is σ = 31650003186. Its totient is φ = 10550001060.

The previous prime is 21100002107. The next prime is 21100002127. The reversal of 21100002122 is 22120000112.

It is a happy number.

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., 18705759361 + 2394242761 = 136769^2 + 48931^2 .

It is not an unprimeable number, because it can be changed into a prime (21100002127) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5275000529 + ... + 5275000532.

Almost surely, 2^21100002122 is an apocalyptic number.

21100002122 is a deficient number, since it is larger than the sum of its proper divisors (10550001064).

21100002122 is a wasteful number, since it uses less digits than its factorization.

21100002122 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10550001063.

The product of its (nonzero) digits is 16, while the sum is 11.

Adding to 21100002122 its reverse (22120000112), we get a palindrome (43220002234).

The spelling of 21100002122 in words is "twenty-one billion, one hundred million, two thousand, one hundred twenty-two".