42421551 has 4 divisors (see below), whose sum is σ = 56562072. Its totient is φ = 28281032.

The previous prime is 42421493. The next prime is 42421553. The reversal of 42421551 is 15512424.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 42421551 - 2¹⁸ = 42159407 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42421553) 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, 7070256 + ... + 7070261.

It is an arithmetic number, because the mean of its divisors is an integer number (14140518).

Almost surely, 2^42421551 is an apocalyptic number.

42421551 is a deficient number, since it is larger than the sum of its proper divisors (14140521).

42421551 is a wasteful number, since it uses less digits than its factorization.

42421551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14140520.

The product of its digits is 1600, while the sum is 24.

The square root of 42421551 is about 6513.1828624721. The cubic root of 42421551 is about 348.7617495817.

Adding to 42421551 its reverse (15512424), we get a palindrome (57933975).

The spelling of 42421551 in words is "forty-two million, four hundred twenty-one thousand, five hundred fifty-one".