661367059 has 4 divisors (see below), whose sum is σ = 670682160. Its totient is φ = 652051960.

The previous prime is 661367041. The next prime is 661367087. The reversal of 661367059 is 950763166.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 661367059 - 2¹⁵ = 661334291 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (661367659) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4657444 + ... + 4657585.

It is an arithmetic number, because the mean of its divisors is an integer number (167670540).

Almost surely, 2^661367059 is an apocalyptic number.

661367059 is a deficient number, since it is larger than the sum of its proper divisors (9315101).

661367059 is an equidigital number, since it uses as much as digits as its factorization.

661367059 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9315100.

The product of its (nonzero) digits is 204120, while the sum is 43.

The square root of 661367059 is about 25717.0577438400. The cubic root of 661367059 is about 871.2594868281.

The spelling of 661367059 in words is "six hundred sixty-one million, three hundred sixty-seven thousand, fifty-nine".