1020866401 has 9 divisors (see below), whose sum is σ = 1035349651. Its totient is φ = 1006584304.

The previous prime is 1020866393. The next prime is 1020866419. The reversal of 1020866401 is 1046680201.

The square root of 1020866401 is 31951.

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., 196028001 + 824838400 = 14001^2 + 28720^2 .

It is not a de Polignac number, because 1020866401 - 2³ = 1020866393 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1020866401.

It is not an unprimeable number, because it can be changed into a prime (1020866701) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 2843460 + ... + 2843818.

Almost surely, 2^1020866401 is an apocalyptic number.

1020866401 is the 31951-st square number.

1020866401 is the 15976-th centered octagonal number.

It is an amenable number.

1020866401 is a deficient number, since it is larger than the sum of its proper divisors (14483250).

1020866401 is an frugal number, since it uses more digits than its factorization.

1020866401 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 896 (or 448 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 28.

The cubic root of 1020866401 is about 1006.9076416200.

Multiplying 1020866401 by its product of nonzero digits (2304), we get a square (2352076187904 = 1533648²).

The spelling of 1020866401 in words is "one billion, twenty million, eight hundred sixty-six thousand, four hundred one".