1021204420405 has 16 divisors (see below), whose sum is σ = 1319862524400. Its totient is φ = 754033218048.

The previous prime is 1021204420363. The next prime is 1021204420429. The reversal of 1021204420405 is 5040244021201.

It can be written as a sum of positive squares in 8 ways, for example, as 72795277636 + 948409142769 = 269806^2 + 973863^2 .

It is a cyclic number.

It is not a de Polignac number, because 1021204420405 - 2³¹ = 1019056936757 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1021204420405.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 335230 + ... + 1467919.

It is an arithmetic number, because the mean of its divisors is an integer number (82491407775).

Almost surely, 2^{1021204420405} is an apocalyptic number.

It is an amenable number.

1021204420405 is a deficient number, since it is larger than the sum of its proper divisors (298658103995).

1021204420405 is a wasteful number, since it uses less digits than its factorization.

1021204420405 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1811880.

The product of its (nonzero) digits is 2560, while the sum is 25.

Adding to 1021204420405 its reverse (5040244021201), we get a palindrome (6061448441606).

The spelling of 1021204420405 in words is "one trillion, twenty-one billion, two hundred four million, four hundred twenty thousand, four hundred five".