1661444361 has 24 divisors (see below), whose sum is σ = 2414607104. Its totient is φ = 1100848320.

The previous prime is 1661444333. The next prime is 1661444383. The reversal of 1661444361 is 1634441661.

1661444361 is a `hidden beast` number, since 1 + 6 + 614 + 4 + 4 + 36 + 1 = 666.

It is not a de Polignac number, because 1661444361 - 2⁶ = 1661444297 is a prime.

It is a super-4 number, since 4×1661444361⁴ (a number of 38 digits) contains 4444 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1661443361) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1772685 + ... + 1773621.

Almost surely, 2^1661444361 is an apocalyptic number.

It is an amenable number.

1661444361 is a deficient number, since it is larger than the sum of its proper divisors (753162743).

1661444361 is a wasteful number, since it uses less digits than its factorization.

1661444361 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1941 (or 1938 counting only the distinct ones).

The product of its digits is 41472, while the sum is 36.

The square root of 1661444361 is about 40760.8189441773. The cubic root of 1661444361 is about 1184.3914602326.

The spelling of 1661444361 in words is "one billion, six hundred sixty-one million, four hundred forty-four thousand, three hundred sixty-one".