4221987 has 32 divisors (see below), whose sum is σ = 7180800. Its totient is φ = 2187360.

The previous prime is 4221977. The next prime is 4221989. The reversal of 4221987 is 7891224.

It is a happy number.

It is not a de Polignac number, because 4221987 - 2⁶ = 4221923 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is an Ulam number.

It is not an unprimeable number, because it can be changed into a prime (4221989) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 11133 + ... + 11505.

It is an arithmetic number, because the mean of its divisors is an integer number (224400).

Almost surely, 2^4221987 is an apocalyptic number.

4221987 is a deficient number, since it is larger than the sum of its proper divisors (2958813).

4221987 is a wasteful number, since it uses less digits than its factorization.

4221987 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 408 (or 394 counting only the distinct ones).

The product of its digits is 8064, while the sum is 33.

The square root of 4221987 is about 2054.7474297344. The cubic root of 4221987 is about 161.6239180320.

The spelling of 4221987 in words is "four million, two hundred twenty-one thousand, nine hundred eighty-seven".