20510221347 has 48 divisors (see below), whose sum is σ = 37456473600. Its totient is φ = 10504569600.

The previous prime is 20510221343. The next prime is 20510221349. The reversal of 20510221347 is 74312201502.

It is not a de Polignac number, because 20510221347 - 2² = 20510221343 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20510221347.

It is not an unprimeable number, because it can be changed into a prime (20510221343) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 159222 + ... + 257627.

It is an arithmetic number, because the mean of its divisors is an integer number (780343200).

Almost surely, 2^20510221347 is an apocalyptic number.

20510221347 is a deficient number, since it is larger than the sum of its proper divisors (16946252253).

20510221347 is a wasteful number, since it uses less digits than its factorization.

20510221347 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 416944 (or 416941 counting only the distinct ones).

The product of its (nonzero) digits is 3360, while the sum is 27.

Adding to 20510221347 its reverse (74312201502), we get a palindrome (94822422849).

The spelling of 20510221347 in words is "twenty billion, five hundred ten million, two hundred twenty-one thousand, three hundred forty-seven".