1392609661 has 4 divisors (see below), whose sum is σ = 1392924924. Its totient is φ = 1392294400.

The previous prime is 1392609643. The next prime is 1392609679. The reversal of 1392609661 is 1669062931.

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

It is an interprime number because it is at equal distance from previous prime (1392609643) and next prime (1392609679).

It can be written as a sum of positive squares in 2 ways, for example, as 1176078436 + 216531225 = 34294^2 + 14715^2 .

It is a cyclic number.

It is not a de Polignac number, because 1392609661 - 2⁵ = 1392609629 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 (1392609641) 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, 150910 + ... + 159871.

It is an arithmetic number, because the mean of its divisors is an integer number (348231231).

Almost surely, 2^1392609661 is an apocalyptic number.

It is an amenable number.

1392609661 is a deficient number, since it is larger than the sum of its proper divisors (315263).

1392609661 is an equidigital number, since it uses as much as digits as its factorization.

1392609661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 315262.

The product of its (nonzero) digits is 104976, while the sum is 43.

The square root of 1392609661 is about 37317.6856329542. The cubic root of 1392609661 is about 1116.7170180707.

The spelling of 1392609661 in words is "one billion, three hundred ninety-two million, six hundred nine thousand, six hundred sixty-one".