101220111 has 10 divisors (see below), whose sum is σ = 151205472. Its totient is φ = 67480020.

The previous prime is 101220107. The next prime is 101220113. The reversal of 101220111 is 111022101.

It is a happy number.

It is not a de Polignac number, because 101220111 - 2² = 101220107 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a junction number, because it is equal to n+sod(n) for n = 101220093 and 101220102.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (101220113) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 624735 + ... + 624896.

Almost surely, 2^101220111 is an apocalyptic number.

101220111 is a deficient number, since it is larger than the sum of its proper divisors (49985361).

101220111 is an equidigital number, since it uses as much as digits as its factorization.

101220111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1249643 (or 1249634 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 9.

The square root of 101220111 is about 10060.8205927747. The cubic root of 101220111 is about 466.0390086277.

Adding to 101220111 its reverse (111022101), we get a palindrome (212242212).

The spelling of 101220111 in words is "one hundred one million, two hundred twenty thousand, one hundred eleven".