42911821 has 8 divisors (see below), whose sum is σ = 44465760. Its totient is φ = 41385552.

The previous prime is 42911797. The next prime is 42911831. The reversal of 42911821 is 12811924.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 42911821 - 2¹³ = 42903629 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 42911821.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42911831) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3735 + ... + 9988.

It is an arithmetic number, because the mean of its divisors is an integer number (5558220).

Almost surely, 2^42911821 is an apocalyptic number.

It is an amenable number.

42911821 is a deficient number, since it is larger than the sum of its proper divisors (1553939).

42911821 is a wasteful number, since it uses less digits than its factorization.

42911821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13835.

The product of its digits is 1152, while the sum is 28.

The square root of 42911821 is about 6550.7114880752. The cubic root of 42911821 is about 350.1001645290.

The spelling of 42911821 in words is "forty-two million, nine hundred eleven thousand, eight hundred twenty-one".