1661667168 has 48 divisors (see below), whose sum is σ = 4985003520. Its totient is φ = 474761856.

The previous prime is 1661667157. The next prime is 1661667169. The reversal of 1661667168 is 8617661661.

It is a tau number, because it is divible by the number of its divisors (48).

It is a super-2 number, since 2×1661667168² = 5522275554418280448, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1661667169) 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, 1235688 + ... + 1237031.

It is an arithmetic number, because the mean of its divisors is an integer number (103854240).

Almost surely, 2^1661667168 is an apocalyptic number.

It is an amenable number.

1661667168 is an abundant number, since it is smaller than the sum of its proper divisors (3323336352).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1661667168 is a wasteful number, since it uses less digits than its factorization.

1661667168 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2472739 (or 2472731 counting only the distinct ones).

The product of its digits is 435456, while the sum is 48.

The square root of 1661667168 is about 40763.5519551474. The cubic root of 1661667168 is about 1184.4444019017. Note that the first 4 decimals are identical.

The spelling of 1661667168 in words is "one billion, six hundred sixty-one million, six hundred sixty-seven thousand, one hundred sixty-eight".