489787400021 has 2 divisors, whose sum is σ = 489787400022. Its totient is φ = 489787400020.

The previous prime is 489787399999. The next prime is 489787400033. The reversal of 489787400021 is 120004787984.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 253800333796 + 235987066225 = 503786^2 + 485785^2 .

It is a cyclic number.

It is not a de Polignac number, because 489787400021 - 2¹⁸ = 489787137877 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (489787400051) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 244893700010 + 244893700011.

It is an arithmetic number, because the mean of its divisors is an integer number (244893700011).

Almost surely, 2^489787400021 is an apocalyptic number.

It is an amenable number.

489787400021 is a deficient number, since it is larger than the sum of its proper divisors (1).

489787400021 is an equidigital number, since it uses as much as digits as its factorization.

489787400021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 903168, while the sum is 50.

The spelling of 489787400021 in words is "four hundred eighty-nine billion, seven hundred eighty-seven million, four hundred thousand, twenty-one".