20420021401 has 12 divisors (see below), whose sum is σ = 22874095980. Its totient is φ = 18199272000.

The previous prime is 20420021399. The next prime is 20420021477. The reversal of 20420021401 is 10412002402.

It can be written as a sum of positive squares in 6 ways, for example, as 432848025 + 19987173376 = 20805^2 + 141376^2 .

It is not a de Polignac number, because 20420021401 - 2¹ = 20420021399 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20420021701) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2078350 + ... + 2088151.

It is an arithmetic number, because the mean of its divisors is an integer number (1906174665).

Almost surely, 2^20420021401 is an apocalyptic number.

It is an amenable number.

20420021401 is a deficient number, since it is larger than the sum of its proper divisors (2454074579).

20420021401 is a wasteful number, since it uses less digits than its factorization.

20420021401 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4166556 (or 4166543 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 16.

Adding to 20420021401 its reverse (10412002402), we get a palindrome (30832023803).

The spelling of 20420021401 in words is "twenty billion, four hundred twenty million, twenty-one thousand, four hundred one".