42555621 has 8 divisors (see below), whose sum is σ = 56885344. Its totient is φ = 28298160.

The previous prime is 42555619. The next prime is 42555659. The reversal of 42555621 is 12655524.

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

It is not a de Polignac number, because 42555621 - 2¹ = 42555619 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 (42557621) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 16675 + ... + 19056.

It is an arithmetic number, because the mean of its divisors is an integer number (7110668).

Almost surely, 2^42555621 is an apocalyptic number.

It is an amenable number.

42555621 is a deficient number, since it is larger than the sum of its proper divisors (14329723).

42555621 is a wasteful number, since it uses less digits than its factorization.

42555621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36131.

The product of its digits is 12000, while the sum is 30.

The square root of 42555621 is about 6523.4669463407. The cubic root of 42555621 is about 349.1287746285.

The spelling of 42555621 in words is "forty-two million, five hundred fifty-five thousand, six hundred twenty-one".