20321500454465 has 64 divisors (see below), whose sum is σ = 28767517286400. Its totient is φ = 13492429998336.

The previous prime is 20321500454419. The next prime is 20321500454467. The reversal of 20321500454465 is 56445400512302.

It is not a de Polignac number, because 20321500454465 - 2¹² = 20321500450369 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20321500454467) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 129996971 + ... + 130153199.

It is an arithmetic number, because the mean of its divisors is an integer number (449492457600).

Almost surely, 2^{20321500454465} is an apocalyptic number.

It is an amenable number.

20321500454465 is a deficient number, since it is larger than the sum of its proper divisors (8446016831935).

20321500454465 is a wasteful number, since it uses less digits than its factorization.

20321500454465 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 157134.

The product of its (nonzero) digits is 576000, while the sum is 41.

Adding to 20321500454465 its reverse (56445400512302), we get a palindrome (76766900966767).

The spelling of 20321500454465 in words is "twenty trillion, three hundred twenty-one billion, five hundred million, four hundred fifty-four thousand, four hundred sixty-five".