101620867721 has 2 divisors, whose sum is σ = 101620867722. Its totient is φ = 101620867720.

The previous prime is 101620867583. The next prime is 101620867763. The reversal of 101620867721 is 127768026101.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 84907549321 + 16713318400 = 291389^2 + 129280^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-101620867721 is a prime.

It is not a weakly prime, because it can be changed into another prime (101620861721) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 50810433860 + 50810433861.

It is an arithmetic number, because the mean of its divisors is an integer number (50810433861).

Almost surely, 2^101620867721 is an apocalyptic number.

It is an amenable number.

101620867721 is a deficient number, since it is larger than the sum of its proper divisors (1).

101620867721 is an equidigital number, since it uses as much as digits as its factorization.

101620867721 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 56448, while the sum is 41.

The spelling of 101620867721 in words is "one hundred one billion, six hundred twenty million, eight hundred sixty-seven thousand, seven hundred twenty-one".