221011209977 has 2 divisors, whose sum is σ = 221011209978. Its totient is φ = 221011209976.

The previous prime is 221011209967. The next prime is 221011210027. The reversal of 221011209977 is 779902110122.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 220271587561 + 739622416 = 469331^2 + 27196^2 .

It is a cyclic number.

It is not a de Polignac number, because 221011209977 - 2⁴ = 221011209961 is a prime.

It is not a weakly prime, because it can be changed into another prime (221011209967) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110505604988 + 110505604989.

It is an arithmetic number, because the mean of its divisors is an integer number (110505604989).

Almost surely, 2^221011209977 is an apocalyptic number.

It is an amenable number.

221011209977 is a deficient number, since it is larger than the sum of its proper divisors (1).

221011209977 is an equidigital number, since it uses as much as digits as its factorization.

221011209977 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 31752, while the sum is 41.

The spelling of 221011209977 in words is "two hundred twenty-one billion, eleven million, two hundred nine thousand, nine hundred seventy-seven".