42551321 has 4 divisors (see below), whose sum is σ = 42729600. Its totient is φ = 42373044.

The previous prime is 42551303. The next prime is 42551351. The reversal of 42551321 is 12315524.

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 42551321 - 2¹⁴ = 42534937 is a prime.

It is a super-2 number, since 2×42551321² = 3621229837690082, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (42551351) 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, 88781 + ... + 89258.

It is an arithmetic number, because the mean of its divisors is an integer number (10682400).

Almost surely, 2^42551321 is an apocalyptic number.

It is an amenable number.

42551321 is a deficient number, since it is larger than the sum of its proper divisors (178279).

42551321 is a wasteful number, since it uses less digits than its factorization.

42551321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 178278.

The product of its digits is 1200, while the sum is 23.

The square root of 42551321 is about 6523.1373586642. The cubic root of 42551321 is about 349.1170150829.

Adding to 42551321 its reverse (12315524), we get a palindrome (54866845).

The spelling of 42551321 in words is "forty-two million, five hundred fifty-one thousand, three hundred twenty-one".