101421989 has 2 divisors, whose sum is σ = 101421990. Its totient is φ = 101421988.

The previous prime is 101421979. The next prime is 101422033. The reversal of 101421989 is 989124101.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 66552964 + 34869025 = 8158^2 + 5905^2 .

It is a cyclic number.

It is not a de Polignac number, because 101421989 - 2²⁴ = 84644773 is a prime.

It is a super-2 number, since 2×101421989² = 20572839705432242, which contains 22 as substring.

It is a Chen prime.

It is equal to p_5838614 and since 101421989 and 5838614 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (101421919) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 50710994 + 50710995.

It is an arithmetic number, because the mean of its divisors is an integer number (50710995).

Almost surely, 2^101421989 is an apocalyptic number.

It is an amenable number.

101421989 is a deficient number, since it is larger than the sum of its proper divisors (1).

101421989 is an equidigital number, since it uses as much as digits as its factorization.

101421989 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5184, while the sum is 35.

The square root of 101421989 is about 10070.8484746818. The cubic root of 101421989 is about 466.3486326851.

The spelling of 101421989 in words is "one hundred one million, four hundred twenty-one thousand, nine hundred eighty-nine".