1020820443669 has 12 divisors (see below), whose sum is σ = 1587942912556. Its totient is φ = 628197196032.

The previous prime is 1020820443653. The next prime is 1020820443683. The reversal of 1020820443669 is 9663440280201.

1020820443669 is a `hidden beast` number, since 1 + 0 + 2 + 0 + 8 + 204 + 436 + 6 + 9 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 413571179025 + 607249264644 = 643095^2 + 779262^2 .

It is not a de Polignac number, because 1020820443669 - 2⁴ = 1020820443653 is a prime.

It is a super-2 number, since 2×1020820443669² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1020821443669) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 4362480412 + ... + 4362480645.

Almost surely, 2^{1020820443669} is an apocalyptic number.

It is an amenable number.

1020820443669 is a deficient number, since it is larger than the sum of its proper divisors (567122468887).

1020820443669 is a wasteful number, since it uses less digits than its factorization.

1020820443669 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8724961076 (or 8724961073 counting only the distinct ones).

The product of its (nonzero) digits is 497664, while the sum is 45.

The spelling of 1020820443669 in words is "one trillion, twenty billion, eight hundred twenty million, four hundred forty-three thousand, six hundred sixty-nine".