1598317661 has 4 divisors (see below), whose sum is σ = 1628474652. Its totient is φ = 1568160672.

The previous prime is 1598317657. The next prime is 1598317681. The reversal of 1598317661 is 1667138951.

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

It can be written as a sum of positive squares in 2 ways, for example, as 1331812036 + 266505625 = 36494^2 + 16325^2 .

It is a cyclic number.

It is not a de Polignac number, because 1598317661 - 2² = 1598317657 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1598317631) 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, 15078416 + ... + 15078521.

It is an arithmetic number, because the mean of its divisors is an integer number (407118663).

Almost surely, 2^1598317661 is an apocalyptic number.

It is an amenable number.

1598317661 is a deficient number, since it is larger than the sum of its proper divisors (30156991).

1598317661 is an equidigital number, since it uses as much as digits as its factorization.

1598317661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30156990.

The product of its digits is 272160, while the sum is 47.

The square root of 1598317661 is about 39978.9652317315. The cubic root of 1598317661 is about 1169.1970191019.

The spelling of 1598317661 in words is "one billion, five hundred ninety-eight million, three hundred seventeen thousand, six hundred sixty-one".