42990221 has 4 divisors (see below), whose sum is σ = 43018272. Its totient is φ = 42962172.

The previous prime is 42990193. The next prime is 42990223. The reversal of 42990221 is 12209924.

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 42990221 - 2¹⁴ = 42973837 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42990223) 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, 11585 + ... + 14838.

It is an arithmetic number, because the mean of its divisors is an integer number (10754568).

Almost surely, 2^42990221 is an apocalyptic number.

It is an amenable number.

42990221 is a deficient number, since it is larger than the sum of its proper divisors (28051).

42990221 is a wasteful number, since it uses less digits than its factorization.

42990221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28050.

The product of its (nonzero) digits is 2592, while the sum is 29.

The square root of 42990221 is about 6556.6928401443. The cubic root of 42990221 is about 350.3132460952.

The spelling of 42990221 in words is "forty-two million, nine hundred ninety thousand, two hundred twenty-one".