64559400191989 has 2 divisors, whose sum is σ = 64559400191990. Its totient is φ = 64559400191988.

The previous prime is 64559400191977. The next prime is 64559400192029. The reversal of 64559400191989 is 98919100495546.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 46733862871089 + 17825537320900 = 6836217^2 + 4222030^2 .

It is a cyclic number.

It is not a de Polignac number, because 64559400191989 - 2⁹ = 64559400191477 is a prime.

It is a super-2 number, since 2×64559400191989² (a number of 28 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (64559400191929) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32279700095994 + 32279700095995.

It is an arithmetic number, because the mean of its divisors is an integer number (32279700095995).

Almost surely, 2^{64559400191989} is an apocalyptic number.

It is an amenable number.

64559400191989 is a deficient number, since it is larger than the sum of its proper divisors (1).

64559400191989 is an equidigital number, since it uses as much as digits as its factorization.

64559400191989 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 125971200, while the sum is 70.

The spelling of 64559400191989 in words is "sixty-four trillion, five hundred fifty-nine billion, four hundred million, one hundred ninety-one thousand, nine hundred eighty-nine".