4640821 has 2 divisors, whose sum is σ = 4640822. Its totient is φ = 4640820.

The previous prime is 4640803. The next prime is 4640833. The reversal of 4640821 is 1280464.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2937796 + 1703025 = 1714^2 + 1305^2 .

It is a cyclic number.

It is not a de Polignac number, because 4640821 - 2⁵ = 4640789 is a prime.

4640821 is a lucky number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (4640221) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2320410 + 2320411.

It is an arithmetic number, because the mean of its divisors is an integer number (2320411).

Almost surely, 2^4640821 is an apocalyptic number.

It is an amenable number.

4640821 is a deficient number, since it is larger than the sum of its proper divisors (1).

4640821 is an equidigital number, since it uses as much as digits as its factorization.

4640821 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1536, while the sum is 25.

The square root of 4640821 is about 2154.2564842655. The cubic root of 4640821 is about 166.8008550430.

The spelling of 4640821 in words is "four million, six hundred forty thousand, eight hundred twenty-one".