2021762640769 has 9 divisors (see below), whose sum is σ = 2033764128643. Its totient is φ = 2009831586952.

The previous prime is 2021762640767. The next prime is 2021762640773. The reversal of 2021762640769 is 9670462671202.

The square root of 2021762640769 is 1421887.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 1839102138225 + 182660502544 = 1356135^2 + 427388^2 .

It is not a de Polignac number, because 2021762640769 - 2¹ = 2021762640767 is a prime.

It is a super-2 number, since 2×2021762640769² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2021762640767) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 245982342 + ... + 245990560.

Almost surely, 2^{2021762640769} is an apocalyptic number.

2021762640769 is the 1421887-th square number.

2021762640769 is the 710944-th centered octagonal number.

It is an amenable number.

2021762640769 is a deficient number, since it is larger than the sum of its proper divisors (12001487874).

2021762640769 is an frugal number, since it uses more digits than its factorization.

2021762640769 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16784 (or 8392 counting only the distinct ones).

The product of its (nonzero) digits is 3048192, while the sum is 52.

The spelling of 2021762640769 in words is "two trillion, twenty-one billion, seven hundred sixty-two million, six hundred forty thousand, seven hundred sixty-nine".