1939304122921 has 45 divisors (see below), whose sum is σ = 2269438474645. Its totient is φ = 1656846688640.

The previous prime is 1939304122907. The next prime is 1939304122933. The reversal of 1939304122921 is 1292214039391.

The square root of 1939304122921 is 1392589.

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 1380129194521 + 559174928400 = 1174789^2 + 747780^2 .

It is a de Polignac number, because none of the positive numbers 2^k-1939304122921 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1939304122961) 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 44 ways as a sum of consecutive naturals, for example, 2864555235 + ... + 2864555911.

Almost surely, 2^{1939304122921} is an apocalyptic number.

1939304122921 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

1939304122921 is the 1392589-th square number.

1939304122921 is the 696295-th centered octagonal number.

It is an amenable number.

1939304122921 is a deficient number, since it is larger than the sum of its proper divisors (330134351724).

1939304122921 is an frugal number, since it uses more digits than its factorization.

1939304122921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1432 (or 705 counting only the distinct ones).

The product of its (nonzero) digits is 209952, while the sum is 46.

The spelling of 1939304122921 in words is "one trillion, nine hundred thirty-nine billion, three hundred four million, one hundred twenty-two thousand, nine hundred twenty-one".