20351442621643 has 12 divisors (see below), whose sum is σ = 23674204561752. Its totient is φ = 17444036621760.

The previous prime is 20351442621641. The next prime is 20351442621647. The reversal of 20351442621643 is 34612624415302.

It is not a de Polignac number, because 20351442621643 - 2¹ = 20351442621641 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20351442621643.

It is not an unprimeable number, because it can be changed into a prime (20351442621641) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 22325763 + ... + 23219443.

It is an arithmetic number, because the mean of its divisors is an integer number (1972850380146).

Almost surely, 2^{20351442621643} is an apocalyptic number.

20351442621643 is a deficient number, since it is larger than the sum of its proper divisors (3322761940109).

20351442621643 is an equidigital number, since it uses as much as digits as its factorization.

20351442621643 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1358442 (or 1358435 counting only the distinct ones).

The product of its (nonzero) digits is 829440, while the sum is 43.

The spelling of 20351442621643 in words is "twenty trillion, three hundred fifty-one billion, four hundred forty-two million, six hundred twenty-one thousand, six hundred forty-three".