21221210101 has 8 divisors (see below), whose sum is σ = 26118412544. Its totient is φ = 16790407920.

The previous prime is 21221210069. The next prime is 21221210111. The reversal of 21221210101 is 10101212212.

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

It is not a de Polignac number, because 21221210101 - 2⁵ = 21221210069 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (13).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21221210111) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 116599965 + ... + 116600146.

It is an arithmetic number, because the mean of its divisors is an integer number (3264801568).

Almost surely, 2^21221210101 is an apocalyptic number.

It is an amenable number.

21221210101 is a deficient number, since it is larger than the sum of its proper divisors (4897202443).

21221210101 is a wasteful number, since it uses less digits than its factorization.

21221210101 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 233200131.

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

Adding to 21221210101 its reverse (10101212212), we get a palindrome (31322422313).

It can be divided in two parts, 212212 and 10101, that multiplied together give a palindrome (2143553412).

The spelling of 21221210101 in words is "twenty-one billion, two hundred twenty-one million, two hundred ten thousand, one hundred one".