102031021 has 4 divisors (see below), whose sum is σ = 102059100. Its totient is φ = 102002944.

The previous prime is 102030953. The next prime is 102031037. The reversal of 102031021 is 120130201.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 120130201 = 1693 ⋅70957.

It can be written as a sum of positive squares in 2 ways, for example, as 60621796 + 41409225 = 7786^2 + 6435^2 .

It is a cyclic number.

It is not a de Polignac number, because 102031021 - 2¹⁹ = 101506733 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 102030989 and 102031007.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (102031051) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7606 + ... + 16183.

It is an arithmetic number, because the mean of its divisors is an integer number (25514775).

Almost surely, 2^102031021 is an apocalyptic number.

It is an amenable number.

102031021 is a deficient number, since it is larger than the sum of its proper divisors (28079).

102031021 is an equidigital number, since it uses as much as digits as its factorization.

102031021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28078.

The product of its (nonzero) digits is 12, while the sum is 10.

The square root of 102031021 is about 10101.0405899590. The cubic root of 102031021 is about 467.2802341488.

Adding to 102031021 its reverse (120130201), we get a palindrome (222161222).

It can be divided in two parts, 1020 and 31021, that added together give a square (32041 = 179²).

The spelling of 102031021 in words is "one hundred two million, thirty-one thousand, twenty-one".