20004721633 has 4 divisors (see below), whose sum is σ = 21543546388. Its totient is φ = 18465896880.

The previous prime is 20004721609. The next prime is 20004721637. The reversal of 20004721633 is 33612740002.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 33612740002 = 2 ⋅16806370001.

It can be written as a sum of positive squares in 2 ways, for example, as 6057820224 + 13946901409 = 77832^2 + 118097^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20004721633 is a prime.

It is a super-2 number, since 2×20004721633² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (20004721637) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 769412358 + ... + 769412383.

It is an arithmetic number, because the mean of its divisors is an integer number (5385886597).

Almost surely, 2^20004721633 is an apocalyptic number.

It is an amenable number.

20004721633 is a deficient number, since it is larger than the sum of its proper divisors (1538824755).

20004721633 is a wasteful number, since it uses less digits than its factorization.

20004721633 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1538824754.

The product of its (nonzero) digits is 6048, while the sum is 28.

The spelling of 20004721633 in words is "twenty billion, four million, seven hundred twenty-one thousand, six hundred thirty-three".