21145190389 has 2 divisors, whose sum is σ = 21145190390. Its totient is φ = 21145190388.

The previous prime is 21145190387. The next prime is 21145190467. The reversal of 21145190389 is 98309154112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21008183364 + 137007025 = 144942^2 + 11705^2 .

It is a cyclic number.

It is not a de Polignac number, because 21145190389 - 2¹ = 21145190387 is a prime.

Together with 21145190387, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21145190387) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10572595194 + 10572595195.

It is an arithmetic number, because the mean of its divisors is an integer number (10572595195).

Almost surely, 2^21145190389 is an apocalyptic number.

It is an amenable number.

21145190389 is a deficient number, since it is larger than the sum of its proper divisors (1).

21145190389 is an equidigital number, since it uses as much as digits as its factorization.

21145190389 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 77760, while the sum is 43.

The spelling of 21145190389 in words is "twenty-one billion, one hundred forty-five million, one hundred ninety thousand, three hundred eighty-nine".