1020020211961 has 2 divisors, whose sum is σ = 1020020211962. Its totient is φ = 1020020211960.

The previous prime is 1020020211943. The next prime is 1020020212009. The reversal of 1020020211961 is 1691120200201.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 689803335936 + 330216876025 = 830544^2 + 574645^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1020020211961 is a prime.

It is not a weakly prime, because it can be changed into another prime (1020020215961) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 510010105980 + 510010105981.

It is an arithmetic number, because the mean of its divisors is an integer number (510010105981).

Almost surely, 2^{1020020211961} is an apocalyptic number.

It is an amenable number.

1020020211961 is a deficient number, since it is larger than the sum of its proper divisors (1).

1020020211961 is an equidigital number, since it uses as much as digits as its factorization.

1020020211961 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 432, while the sum is 25.

The spelling of 1020020211961 in words is "one trillion, twenty billion, twenty million, two hundred eleven thousand, nine hundred sixty-one".