21101106977 has 2 divisors, whose sum is σ = 21101106978. Its totient is φ = 21101106976.

The previous prime is 21101106947. The next prime is 21101106989. The reversal of 21101106977 is 77960110112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20952852001 + 148254976 = 144751^2 + 12176^2 .

It is a cyclic number.

It is not a de Polignac number, because 21101106977 - 2¹² = 21101102881 is a prime.

It is not a weakly prime, because it can be changed into another prime (21101106947) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10550553488 + 10550553489.

It is an arithmetic number, because the mean of its divisors is an integer number (10550553489).

Almost surely, 2^21101106977 is an apocalyptic number.

It is an amenable number.

21101106977 is a deficient number, since it is larger than the sum of its proper divisors (1).

21101106977 is an equidigital number, since it uses as much as digits as its factorization.

21101106977 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5292, while the sum is 35.

The spelling of 21101106977 in words is "twenty-one billion, one hundred one million, one hundred six thousand, nine hundred seventy-seven".