20355410021 has 16 divisors (see below), whose sum is σ = 21322465920. Its totient is φ = 19395340800.

The previous prime is 20355409951. The next prime is 20355410027. The reversal of 20355410021 is 12001455302.

It is a cyclic number.

It is not a de Polignac number, because 20355410021 - 2¹⁸ = 20355147877 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (23).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20355410027) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 11610881 + ... + 11612633.

It is an arithmetic number, because the mean of its divisors is an integer number (1332654120).

Almost surely, 2^20355410021 is an apocalyptic number.

It is an amenable number.

20355410021 is a deficient number, since it is larger than the sum of its proper divisors (967055899).

20355410021 is a wasteful number, since it uses less digits than its factorization.

20355410021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3436.

The product of its (nonzero) digits is 1200, while the sum is 23.

Adding to 20355410021 its reverse (12001455302), we get a palindrome (32356865323).

The spelling of 20355410021 in words is "twenty billion, three hundred fifty-five million, four hundred ten thousand, twenty-one".