42064921 has 4 divisors (see below), whose sum is σ = 42323152. Its totient is φ = 41806692.

The previous prime is 42064909. The next prime is 42064931. The reversal of 42064921 is 12946024.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 42064921 - 2⁵ = 42064889 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 42064921.

It is not an unprimeable number, because it can be changed into a prime (42064901) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 128871 + ... + 129196.

It is an arithmetic number, because the mean of its divisors is an integer number (10580788).

Almost surely, 2^42064921 is an apocalyptic number.

It is an amenable number.

42064921 is a deficient number, since it is larger than the sum of its proper divisors (258231).

42064921 is a wasteful number, since it uses less digits than its factorization.

42064921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 258230.

The product of its (nonzero) digits is 3456, while the sum is 28.

The square root of 42064921 is about 6485.7475282345. The cubic root of 42064921 is about 347.7816731803.

It can be divided in two parts, 420 and 64921, that added together give a triangular number (65341 = T₃₆₁).

The spelling of 42064921 in words is "forty-two million, sixty-four thousand, nine hundred twenty-one".