101561477021 has 2 divisors, whose sum is σ = 101561477022. Its totient is φ = 101561477020.

The previous prime is 101561477011. The next prime is 101561477033. The reversal of 101561477021 is 120774165101.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 75963076996 + 25598400025 = 275614^2 + 159995^2 .

It is a cyclic number.

It is not a de Polignac number, because 101561477021 - 2¹⁰ = 101561475997 is a prime.

It is a super-2 number, since 2×101561477021² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (101561477011) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 50780738510 + 50780738511.

It is an arithmetic number, because the mean of its divisors is an integer number (50780738511).

Almost surely, 2^101561477021 is an apocalyptic number.

It is an amenable number.

101561477021 is a deficient number, since it is larger than the sum of its proper divisors (1).

101561477021 is an equidigital number, since it uses as much as digits as its factorization.

101561477021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 11760, while the sum is 35.

The spelling of 101561477021 in words is "one hundred one billion, five hundred sixty-one million, four hundred seventy-seven thousand, twenty-one".