42121566 has 16 divisors (see below), whose sum is σ = 93603600. Its totient is φ = 14040504.

The previous prime is 42121561. The next prime is 42121567. The reversal of 42121566 is 66512124.

42121566 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42121561) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 389961 + ... + 390068.

It is an arithmetic number, because the mean of its divisors is an integer number (5850225).

Almost surely, 2^42121566 is an apocalyptic number.

42121566 is an abundant number, since it is smaller than the sum of its proper divisors (51482034).

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

42121566 is a wasteful number, since it uses less digits than its factorization.

42121566 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 780040 (or 780034 counting only the distinct ones).

The product of its digits is 2880, while the sum is 27.

The square root of 42121566 is about 6490.1129420065. The cubic root of 42121566 is about 347.9377118006.

It can be divided in two parts, 4212 and 1566, that added together give a triangular number (5778 = T₁₀₇).

The spelling of 42121566 in words is "forty-two million, one hundred twenty-one thousand, five hundred sixty-six".