154821509989 has 2 divisors, whose sum is σ = 154821509990. Its totient is φ = 154821509988.

The previous prime is 154821509959. The next prime is 154821510083. The reversal of 154821509989 is 989905128451.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 79542613089 + 75278896900 = 282033^2 + 274370^2 .

It is a cyclic number.

It is not a de Polignac number, because 154821509989 - 2¹⁷ = 154821378917 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (154821509929) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 77410754994 + 77410754995.

It is an arithmetic number, because the mean of its divisors is an integer number (77410754995).

Almost surely, 2^154821509989 is an apocalyptic number.

It is an amenable number.

154821509989 is a deficient number, since it is larger than the sum of its proper divisors (1).

154821509989 is an equidigital number, since it uses as much as digits as its factorization.

154821509989 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 9331200, while the sum is 61.

The spelling of 154821509989 in words is "one hundred fifty-four billion, eight hundred twenty-one million, five hundred nine thousand, nine hundred eighty-nine".