21001212210122 has 8 divisors (see below), whose sum is σ = 31881358295136. Its totient is φ = 10374092778412.

The previous prime is 21001212210109. The next prime is 21001212210137. The reversal of 21001212210122 is 22101221210012.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a self number, because there is not a number n which added to its sum of digits gives 21001212210122.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 63256663118 + ... + 63256663449.

It is an arithmetic number, because the mean of its divisors is an integer number (3985169786892).

Almost surely, 2^{21001212210122} is an apocalyptic number.

21001212210122 is a deficient number, since it is larger than the sum of its proper divisors (10880146085014).

21001212210122 is a wasteful number, since it uses less digits than its factorization.

21001212210122 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 126513326652.

The product of its (nonzero) digits is 64, while the sum is 17.

Adding to 21001212210122 its reverse (22101221210012), we get a palindrome (43102433420134).

The spelling of 21001212210122 in words is "twenty-one trillion, one billion, two hundred twelve million, two hundred ten thousand, one hundred twenty-two".