102021111 has 6 divisors (see below), whose sum is σ = 147363840. Its totient is φ = 68014068.

The previous prime is 102021109. The next prime is 102021113. The reversal of 102021111 is 111120201.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (102021109) and next prime (102021113).

It is not a de Polignac number, because 102021111 - 2¹ = 102021109 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9), and also a Moran number because the ratio is a prime number: 11335679 = 102021111 / (1 + 0 + 2 + 0 + 2 + 1 + 1 + 1 + 1).

It is a junction number, because it is equal to n+sod(n) for n = 102021093 and 102021102.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (102021113) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 5667831 + ... + 5667848.

It is an arithmetic number, because the mean of its divisors is an integer number (24560640).

Almost surely, 2^102021111 is an apocalyptic number.

102021111 is a deficient number, since it is larger than the sum of its proper divisors (45342729).

102021111 is a wasteful number, since it uses less digits than its factorization.

102021111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11335685 (or 11335682 counting only the distinct ones).

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

The square root of 102021111 is about 10100.5500345278. The cubic root of 102021111 is about 467.2651050994.

Adding to 102021111 its reverse (111120201), we get a palindrome (213141312).

The spelling of 102021111 in words is "one hundred two million, twenty-one thousand, one hundred eleven".