4221651 has 8 divisors (see below), whose sum is σ = 6433024. Its totient is φ = 2412360.

The previous prime is 4221649. The next prime is 4221653. The reversal of 4221651 is 1561224.

It is an interprime number because it is at equal distance from previous prime (4221649) and next prime (4221653).

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

It is not a de Polignac number, because 4221651 - 2¹ = 4221649 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21), and also a Moran number because the ratio is a prime number: 201031 = 4221651 / (4 + 2 + 2 + 1 + 6 + 5 + 1).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (4221653) 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, 100495 + ... + 100536.

It is an arithmetic number, because the mean of its divisors is an integer number (804128).

Almost surely, 2^4221651 is an apocalyptic number.

4221651 is a deficient number, since it is larger than the sum of its proper divisors (2211373).

4221651 is a wasteful number, since it uses less digits than its factorization.

4221651 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 201041.

The product of its digits is 480, while the sum is 21.

The square root of 4221651 is about 2054.6656662338. The cubic root of 4221651 is about 161.6196303923.

Adding to 4221651 its reverse (1561224), we get a palindrome (5782875).

The spelling of 4221651 in words is "four million, two hundred twenty-one thousand, six hundred fifty-one".