2021812729 has 2 divisors, whose sum is σ = 2021812730. Its totient is φ = 2021812728.

The previous prime is 2021812711. The next prime is 2021812799. The reversal of 2021812729 is 9272181202.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1141088400 + 880724329 = 33780^2 + 29677^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2021812729 is a prime.

It is a super-2 number, since 2×2021812729² = 8175453422292854882, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 2021812694 and 2021812703.

It is not a weakly prime, because it can be changed into another prime (2021812799) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1010906364 + 1010906365.

It is an arithmetic number, because the mean of its divisors is an integer number (1010906365).

Almost surely, 2^2021812729 is an apocalyptic number.

It is an amenable number.

2021812729 is a deficient number, since it is larger than the sum of its proper divisors (1).

2021812729 is an equidigital number, since it uses as much as digits as its factorization.

2021812729 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8064, while the sum is 34.

The square root of 2021812729 is about 44964.5719316886. The cubic root of 2021812729 is about 1264.4848843456.

The spelling of 2021812729 in words is "two billion, twenty-one million, eight hundred twelve thousand, seven hundred twenty-nine".