21146531232061 has 2 divisors, whose sum is σ = 21146531232062. Its totient is φ = 21146531232060.

The previous prime is 21146531232023. The next prime is 21146531232077. The reversal of 21146531232061 is 16023213564112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18675630183961 + 2470901048100 = 4321531^2 + 1571910^2 .

It is a cyclic number.

It is not a de Polignac number, because 21146531232061 - 2¹³ = 21146531223869 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21146531232061.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21146531332061) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10573265616030 + 10573265616031.

It is an arithmetic number, because the mean of its divisors is an integer number (10573265616031).

Almost surely, 2^{21146531232061} is an apocalyptic number.

It is an amenable number.

21146531232061 is a deficient number, since it is larger than the sum of its proper divisors (1).

21146531232061 is an equidigital number, since it uses as much as digits as its factorization.

21146531232061 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 51840, while the sum is 37.

Adding to 21146531232061 its reverse (16023213564112), we get a palindrome (37169744796173).

The spelling of 21146531232061 in words is "twenty-one trillion, one hundred forty-six billion, five hundred thirty-one million, two hundred thirty-two thousand, sixty-one".