20321516 has 12 divisors (see below), whose sum is σ = 35611632. Its totient is φ = 10146768.

The previous prime is 20321447. The next prime is 20321537. The reversal of 20321516 is 61512302.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 206 + ... + 6378.

It is an arithmetic number, because the mean of its divisors is an integer number (2967636).

Almost surely, 2^20321516 is an apocalyptic number.

It is an amenable number.

20321516 is a deficient number, since it is larger than the sum of its proper divisors (15290116).

20321516 is a wasteful number, since it uses less digits than its factorization.

20321516 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7000 (or 6998 counting only the distinct ones).

The product of its (nonzero) digits is 360, while the sum is 20.

The square root of 20321516 is about 4507.9392187562. The cubic root of 20321516 is about 272.8885840174. Note that the first 3 decimals are identical.

Adding to 20321516 its reverse (61512302), we get a palindrome (81833818).

The spelling of 20321516 in words is "twenty million, three hundred twenty-one thousand, five hundred sixteen".