20511222464 has 14 divisors (see below), whose sum is σ = 40701957204. Its totient is φ = 10255611200.

The previous prime is 20511222443. The next prime is 20511222469. The reversal of 20511222464 is 46422211502.

It is not an unprimeable number, because it can be changed into a prime (20511222469) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 160243862 + ... + 160243989.

Almost surely, 2^20511222464 is an apocalyptic number.

It is an amenable number.

20511222464 is a deficient number, since it is larger than the sum of its proper divisors (20190734740).

20511222464 is an equidigital number, since it uses as much as digits as its factorization.

20511222464 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 320487863 (or 320487853 counting only the distinct ones).

The product of its (nonzero) digits is 7680, while the sum is 29.

Adding to 20511222464 its reverse (46422211502), we get a palindrome (66933433966).

The spelling of 20511222464 in words is "twenty billion, five hundred eleven million, two hundred twenty-two thousand, four hundred sixty-four".