1031421016921 has 9 divisors (see below), whose sum is σ = 1048669734333. Its totient is φ = 1014451540320.

The previous prime is 1031421016889. The next prime is 1031421016949. The reversal of 1031421016921 is 1296101241301.

The square root of 1031421016921 is 1015589.

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

It can be written as a sum of positive squares in 4 ways, for example, as 102009333321 + 929411683600 = 319389^2 + 964060^2 .

It is not a de Polignac number, because 1031421016921 - 2⁵ = 1031421016889 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1031421016961) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 61942605 + ... + 61959253.

Almost surely, 2^{1031421016921} is an apocalyptic number.

1031421016921 is the 1015589-th square number.

1031421016921 is the 507795-th centered octagonal number.

It is an amenable number.

1031421016921 is a deficient number, since it is larger than the sum of its proper divisors (17248717412).

1031421016921 is an frugal number, since it uses more digits than its factorization.

1031421016921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33420 (or 16710 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 31.

The spelling of 1031421016921 in words is "one trillion, thirty-one billion, four hundred twenty-one million, sixteen thousand, nine hundred twenty-one".