20005102547621 has 8 divisors (see below), whose sum is σ = 20695750204440. Its totient is φ = 19322348007168.

The previous prime is 20005102547611. The next prime is 20005102547659. The reversal of 20005102547621 is 12674520150002.

It can be written as a sum of positive squares in 4 ways, for example, as 5053818724900 + 14951283822721 = 2248070^2 + 3866689^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20005102547621 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20005102547611) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1973273936 + ... + 1973284073.

It is an arithmetic number, because the mean of its divisors is an integer number (2586968775555).

Almost surely, 2^{20005102547621} is an apocalyptic number.

It is an amenable number.

20005102547621 is a deficient number, since it is larger than the sum of its proper divisors (690647656819).

20005102547621 is a wasteful number, since it uses less digits than its factorization.

20005102547621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3946558183.

The product of its (nonzero) digits is 33600, while the sum is 35.

Adding to 20005102547621 its reverse (12674520150002), we get a palindrome (32679622697623).

The spelling of 20005102547621 in words is "twenty trillion, five billion, one hundred two million, five hundred forty-seven thousand, six hundred twenty-one".