20521332401 has 2 divisors, whose sum is σ = 20521332402. Its totient is φ = 20521332400.

The previous prime is 20521332367. The next prime is 20521332407. The reversal of 20521332401 is 10423312502.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19530342001 + 990990400 = 139751^2 + 31480^2 .

It is a cyclic number.

It is not a de Polignac number, because 20521332401 - 2¹⁴ = 20521316017 is a prime.

It is a super-2 number, since 2×20521332401² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (20521332407) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10260666200 + 10260666201.

It is an arithmetic number, because the mean of its divisors is an integer number (10260666201).

Almost surely, 2^20521332401 is an apocalyptic number.

It is an amenable number.

20521332401 is a deficient number, since it is larger than the sum of its proper divisors (1).

20521332401 is an equidigital number, since it uses as much as digits as its factorization.

20521332401 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1440, while the sum is 23.

Adding to 20521332401 its reverse (10423312502), we get a palindrome (30944644903).

The spelling of 20521332401 in words is "twenty billion, five hundred twenty-one million, three hundred thirty-two thousand, four hundred one".