21211020200977 has 2 divisors, whose sum is σ = 21211020200978. Its totient is φ = 21211020200976.

The previous prime is 21211020200963. The next prime is 21211020201001. The reversal of 21211020200977 is 77900202011212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15778023288336 + 5432996912641 = 3972156^2 + 2330879^2 .

It is a cyclic number.

It is not a de Polignac number, because 21211020200977 - 2⁷ = 21211020200849 is a prime.

It is not a weakly prime, because it can be changed into another prime (21211020200927) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10605510100488 + 10605510100489.

It is an arithmetic number, because the mean of its divisors is an integer number (10605510100489).

Almost surely, 2^{21211020200977} is an apocalyptic number.

It is an amenable number.

21211020200977 is a deficient number, since it is larger than the sum of its proper divisors (1).

21211020200977 is an equidigital number, since it uses as much as digits as its factorization.

21211020200977 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 7056, while the sum is 34.

The spelling of 21211020200977 in words is "twenty-one trillion, two hundred eleven billion, twenty million, two hundred thousand, nine hundred seventy-seven".