1666623042 has 96 divisors (see below), whose sum is σ = 4253932800. Its totient is φ = 461614464.

The previous prime is 1666623041. The next prime is 1666623043. The reversal of 1666623042 is 2403266661.

It is an interprime number because it is at equal distance from previous prime (1666623041) and next prime (1666623043).

It is a junction number, because it is equal to n+sod(n) for n = 1666622988 and 1666623006.

It is not an unprimeable number, because it can be changed into a prime (1666623041) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1813059 + ... + 1813977.

It is an arithmetic number, because the mean of its divisors is an integer number (44311800).

Almost surely, 2^1666623042 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1666623042, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2126966400).

1666623042 is an abundant number, since it is smaller than the sum of its proper divisors (2587309758).

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

1666623042 is a wasteful number, since it uses less digits than its factorization.

1666623042 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1360 (or 1357 counting only the distinct ones).

The product of its (nonzero) digits is 62208, while the sum is 36.

The square root of 1666623042 is about 40824.2947520224. The cubic root of 1666623042 is about 1185.6207568541.

The spelling of 1666623042 in words is "one billion, six hundred sixty-six million, six hundred twenty-three thousand, forty-two".