103121310020021 has 4 divisors (see below), whose sum is σ = 103121330418444. Its totient is φ = 103121289621600.

The previous prime is 103121310020009. The next prime is 103121310020033. The reversal of 103121310020021 is 120020013121301.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (103121310020009) and next prime (103121310020033).

It can be written as a sum of positive squares in 2 ways, for example, as 92350370208100 + 10770939811921 = 9609910^2 + 3281911^2 .

It is a cyclic number.

It is not a de Polignac number, because 103121310020021 - 2¹⁴ = 103121310003637 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (103121310020221) 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, 3674531 + ... + 14823791.

It is an arithmetic number, because the mean of its divisors is an integer number (25780332604611).

Almost surely, 2^{103121310020021} is an apocalyptic number.

It is an amenable number.

103121310020021 is a deficient number, since it is larger than the sum of its proper divisors (20398423).

103121310020021 is an equidigital number, since it uses as much as digits as its factorization.

103121310020021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20398422.

The product of its (nonzero) digits is 72, while the sum is 17.

Adding to 103121310020021 its reverse (120020013121301), we get a palindrome (223141323141322).

The spelling of 103121310020021 in words is "one hundred three trillion, one hundred twenty-one billion, three hundred ten million, twenty thousand, twenty-one".