1621531247101 has 2 divisors, whose sum is σ = 1621531247102. Its totient is φ = 1621531247100.

The previous prime is 1621531247047. The next prime is 1621531247177. The reversal of 1621531247101 is 1017421351261.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1519546824601 + 101984422500 = 1232699^2 + 319350^2 .

It is a cyclic number.

It is not a de Polignac number, because 1621531247101 - 2¹¹ = 1621531245053 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1621531242101) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 810765623550 + 810765623551.

It is an arithmetic number, because the mean of its divisors is an integer number (810765623551).

Almost surely, 2^{1621531247101} is an apocalyptic number.

It is an amenable number.

1621531247101 is a deficient number, since it is larger than the sum of its proper divisors (1).

1621531247101 is an equidigital number, since it uses as much as digits as its factorization.

1621531247101 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 10080, while the sum is 34.

Adding to 1621531247101 its reverse (1017421351261), we get a palindrome (2638952598362).

The spelling of 1621531247101 in words is "one trillion, six hundred twenty-one billion, five hundred thirty-one million, two hundred forty-seven thousand, one hundred one".