1663322021 has 4 divisors (see below), whose sum is σ = 1663435200. Its totient is φ = 1663208844.

The previous prime is 1663321987. The next prime is 1663322033. The reversal of 1663322021 is 1202233661.

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, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 1663322021 - 2¹⁸ = 1663059877 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 (1663322051) 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, 30551 + ... + 65268.

It is an arithmetic number, because the mean of its divisors is an integer number (415858800).

Almost surely, 2^1663322021 is an apocalyptic number.

It is an amenable number.

1663322021 is a deficient number, since it is larger than the sum of its proper divisors (113179).

1663322021 is an equidigital number, since it uses as much as digits as its factorization.

1663322021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 113178.

The product of its (nonzero) digits is 2592, while the sum is 26.

The square root of 1663322021 is about 40783.8450982739. The cubic root of 1663322021 is about 1184.8374671894.

Adding to 1663322021 its reverse (1202233661), we get a palindrome (2865555682).

The spelling of 1663322021 in words is "one billion, six hundred sixty-three million, three hundred twenty-two thousand, twenty-one".