1611961909 has 8 divisors (see below), whose sum is σ = 1619987040. Its totient is φ = 1603950000.

The previous prime is 1611961907. The next prime is 1611961937. The reversal of 1611961909 is 9091691161.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1611961909 - 2¹ = 1611961907 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 (1611961903) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 313459 + ... + 318559.

It is an arithmetic number, because the mean of its divisors is an integer number (202498380).

Almost surely, 2^1611961909 is an apocalyptic number.

It is an amenable number.

1611961909 is a deficient number, since it is larger than the sum of its proper divisors (8025131).

1611961909 is a wasteful number, since it uses less digits than its factorization.

1611961909 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6611.

The product of its (nonzero) digits is 26244, while the sum is 43.

The square root of 1611961909 is about 40149.2454350016. The cubic root of 1611961909 is about 1172.5145977697.

The spelling of 1611961909 in words is "one billion, six hundred eleven million, nine hundred sixty-one thousand, nine hundred nine".