42687321 has 4 divisors (see below), whose sum is σ = 56916432. Its totient is φ = 28458212.

The previous prime is 42687299. The next prime is 42687331. The reversal of 42687321 is 12378624.

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 42687321 - 2⁷ = 42687193 is a prime.

It is a super-3 number, since 3×42687321³ (a number of 24 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (42687331) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7114551 + ... + 7114556.

It is an arithmetic number, because the mean of its divisors is an integer number (14229108).

Almost surely, 2^42687321 is an apocalyptic number.

It is an amenable number.

42687321 is a deficient number, since it is larger than the sum of its proper divisors (14229111).

42687321 is a wasteful number, since it uses less digits than its factorization.

42687321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14229110.

The product of its digits is 16128, while the sum is 33.

The square root of 42687321 is about 6533.5534741823. The cubic root of 42687321 is about 349.4885618677.

The spelling of 42687321 in words is "forty-two million, six hundred eighty-seven thousand, three hundred twenty-one".