42691921 has 8 divisors (see below), whose sum is σ = 43243200. Its totient is φ = 42143760.

The previous prime is 42691919. The next prime is 42691951. The reversal of 42691921 is 12919624.

42691921 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is not a de Polignac number, because 42691921 - 2¹ = 42691919 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (42691951) 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, 38586 + ... + 39676.

It is an arithmetic number, because the mean of its divisors is an integer number (5405400).

Almost surely, 2^42691921 is an apocalyptic number.

It is an amenable number.

42691921 is a deficient number, since it is larger than the sum of its proper divisors (551279).

42691921 is a wasteful number, since it uses less digits than its factorization.

42691921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1559.

The product of its digits is 7776, while the sum is 34.

The square root of 42691921 is about 6533.9054936539. The cubic root of 42691921 is about 349.5011150849.

The spelling of 42691921 in words is "forty-two million, six hundred ninety-one thousand, nine hundred twenty-one".