101212221 has 32 divisors (see below), whose sum is σ = 155750400. Its totient is φ = 57818880.

The previous prime is 101212219. The next prime is 101212249. The reversal of 101212221 is 122212101.

It is not a de Polignac number, because 101212221 - 2¹ = 101212219 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 101212197 and 101212206.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (101212211) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 211060 + ... + 211538.

It is an arithmetic number, because the mean of its divisors is an integer number (4867200).

Almost surely, 2^101212221 is an apocalyptic number.

101212221 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

101212221 is a deficient number, since it is larger than the sum of its proper divisors (54538179).

101212221 is a wasteful number, since it uses less digits than its factorization.

101212221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 849.

The product of its (nonzero) digits is 16, while the sum is 12.

The square root of 101212221 is about 10060.4284700007. The cubic root of 101212221 is about 466.0268992313.

Adding to 101212221 its reverse (122212101), we get a palindrome (223424322).

The spelling of 101212221 in words is "one hundred one million, two hundred twelve thousand, two hundred twenty-one".