101431021 has 2 divisors, whose sum is σ = 101431022. Its totient is φ = 101431020.

The previous prime is 101431019. The next prime is 101431049. The reversal of 101431021 is 120134101.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 89775625 + 11655396 = 9475^2 + 3414^2 .

It is a cyclic number.

It is not a de Polignac number, because 101431021 - 2¹ = 101431019 is a prime.

It is a super-2 number, since 2×101431021² = 20576504042204882, which contains 22 as substring.

Together with 101431019, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 101430992 and 101431010.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (101431051) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 50715510 + 50715511.

It is an arithmetic number, because the mean of its divisors is an integer number (50715511).

Almost surely, 2^101431021 is an apocalyptic number.

It is an amenable number.

101431021 is a deficient number, since it is larger than the sum of its proper divisors (1).

101431021 is an equidigital number, since it uses as much as digits as its factorization.

101431021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 24, while the sum is 13.

The square root of 101431021 is about 10071.2968876903. The cubic root of 101431021 is about 466.3624756260.

Adding to 101431021 its reverse (120134101), we get a palindrome (221565122).

The spelling of 101431021 in words is "one hundred one million, four hundred thirty-one thousand, twenty-one".