101240021 has 4 divisors (see below), whose sum is σ = 103394112. Its totient is φ = 99085932.

The previous prime is 101239979. The next prime is 101240023. The reversal of 101240021 is 120042101.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 101240021 - 2²⁶ = 34131157 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 101239984 and 101240011.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (101240023) 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, 1076975 + ... + 1077068.

It is an arithmetic number, because the mean of its divisors is an integer number (25848528).

Almost surely, 2^101240021 is an apocalyptic number.

It is an amenable number.

101240021 is a deficient number, since it is larger than the sum of its proper divisors (2154091).

101240021 is an equidigital number, since it uses as much as digits as its factorization.

101240021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2154090.

The product of its (nonzero) digits is 16, while the sum is 11.

The square root of 101240021 is about 10061.8100260341. The cubic root of 101240021 is about 466.0695632551.

Adding to 101240021 its reverse (120042101), we get a palindrome (221282122).

The spelling of 101240021 in words is "one hundred one million, two hundred forty thousand, twenty-one".