42552021 has 4 divisors (see below), whose sum is σ = 56736032. Its totient is φ = 28368012.

The previous prime is 42552017. The next prime is 42552023. The reversal of 42552021 is 12025524.

It is a happy number.

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 not a de Polignac number, because 42552021 - 2² = 42552017 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42552023) 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, 7092001 + ... + 7092006.

It is an arithmetic number, because the mean of its divisors is an integer number (14184008).

Almost surely, 2^42552021 is an apocalyptic number.

It is an amenable number.

42552021 is a deficient number, since it is larger than the sum of its proper divisors (14184011).

42552021 is a wasteful number, since it uses less digits than its factorization.

42552021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14184010.

The product of its (nonzero) digits is 800, while the sum is 21.

The square root of 42552021 is about 6523.1910136068. The cubic root of 42552021 is about 349.1189294815.

Adding to 42552021 its reverse (12025524), we get a palindrome (54577545).

The spelling of 42552021 in words is "forty-two million, five hundred fifty-two thousand, twenty-one".