42109956 has 84 divisors (see below), whose sum is σ = 126333312. Its totient is φ = 12025584.

The previous prime is 42109939. The next prime is 42109973. The reversal of 42109956 is 65990124.

It is an interprime number because it is at equal distance from previous prime (42109939) and next prime (42109973).

It is a tau number, because it is divible by the number of its divisors (84).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 42109956.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 27 ways as a sum of consecutive naturals, for example, 19381 + ... + 21443.

It is an arithmetic number, because the mean of its divisors is an integer number (1503968).

Almost surely, 2^42109956 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 42109956, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (63166656).

42109956 is an abundant number, since it is smaller than the sum of its proper divisors (84223356).

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

42109956 is a wasteful number, since it uses less digits than its factorization.

42109956 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2092 (or 2075 counting only the distinct ones).

The product of its (nonzero) digits is 19440, while the sum is 36.

The square root of 42109956 is about 6489.2184429252. The cubic root of 42109956 is about 347.9057414157.

The spelling of 42109956 in words is "forty-two million, one hundred nine thousand, nine hundred fifty-six".