166109438 has 32 divisors (see below), whose sum is σ = 287124480. Its totient is φ = 71280000.

The previous prime is 166109423. The next prime is 166109443. The reversal of 166109438 is 834901661.

It is a super-4 number, since 4×166109438⁴ (a number of 34 digits) contains 4444 as substring.

It is a Smith number, since the sum of its digits (38) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Harshad number since it is a multiple of its sum of digits (38).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 167123 + ... + 168113.

It is an arithmetic number, because the mean of its divisors is an integer number (8972640).

Almost surely, 2^166109438 is an apocalyptic number.

166109438 is a deficient number, since it is larger than the sum of its proper divisors (121015042).

166109438 is a wasteful number, since it uses less digits than its factorization.

166109438 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1424.

The product of its (nonzero) digits is 31104, while the sum is 38.

The square root of 166109438 is about 12888.3450450397. The cubic root of 166109438 is about 549.7072138633.

The spelling of 166109438 in words is "one hundred sixty-six million, one hundred nine thousand, four hundred thirty-eight".