661260589999 has 2 divisors, whose sum is σ = 661260590000. Its totient is φ = 661260589998.

The previous prime is 661260589981. The next prime is 661260590033. The reversal of 661260589999 is 999985062166.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 661260589999 - 2⁵ = 661260589967 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (661260589949) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 330630294999 + 330630295000.

It is an arithmetic number, because the mean of its divisors is an integer number (330630295000).

Almost surely, 2^661260589999 is an apocalyptic number.

661260589999 is a deficient number, since it is larger than the sum of its proper divisors (1).

661260589999 is an equidigital number, since it uses as much as digits as its factorization.

661260589999 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 113374080, while the sum is 70.

The spelling of 661260589999 in words is "six hundred sixty-one billion, two hundred sixty million, five hundred eighty-nine thousand, nine hundred ninety-nine".