4891521 has 16 divisors (see below), whose sum is σ = 6796800. Its totient is φ = 3125760.

The previous prime is 4891519. The next prime is 4891547. The reversal of 4891521 is 1251984.

It is a happy number.

It is not a de Polignac number, because 4891521 - 2¹ = 4891519 is a prime.

It is not an unprimeable number, because it can be changed into a prime (4891501) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 13681 + ... + 14033.

It is an arithmetic number, because the mean of its divisors is an integer number (424800).

Almost surely, 2^4891521 is an apocalyptic number.

It is an amenable number.

4891521 is a deficient number, since it is larger than the sum of its proper divisors (1905279).

4891521 is a wasteful number, since it uses less digits than its factorization.

With its successor (4891522) it forms an eRAP, since the sums of their prime factors are consecutive (536 and 537).

4891521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 536.

The product of its digits is 2880, while the sum is 30.

The square root of 4891521 is about 2211.6783219989. The cubic root of 4891521 is about 169.7518987614.

The spelling of 4891521 in words is "four million, eight hundred ninety-one thousand, five hundred twenty-one".