1961338369 has 9 divisors (see below), whose sum is σ = 1994065731. Its totient is φ = 1929141720.

The previous prime is 1961338319. The next prime is 1961338391. The reversal of 1961338369 is 9638331691.

The square root of 1961338369 is 44287.

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., 1557328369 + 404010000 = 39463^2 + 20100^2 .

It is not a de Polignac number, because 1961338369 - 2¹⁵ = 1961305601 is a prime.

It is a super-2 number, since 2×1961338369² = 7693696395423160322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1961338319) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 2966899 + ... + 2967559.

It is an arithmetic number, because the mean of its divisors is an integer number (221562859).

Almost surely, 2^1961338369 is an apocalyptic number.

1961338369 is the 44287-th square number.

1961338369 is the 22144-th centered octagonal number.

It is an amenable number.

1961338369 is a deficient number, since it is larger than the sum of its proper divisors (32727362).

1961338369 is an frugal number, since it uses more digits than its factorization.

1961338369 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1456 (or 728 counting only the distinct ones).

The product of its digits is 629856, while the sum is 49.

The cubic root of 1961338369 is about 1251.7497349858.

Multiplying 1961338369 by its sum of digits (49), we get a square (96105580081 = 310009²).

The spelling of 1961338369 in words is "one billion, nine hundred sixty-one million, three hundred thirty-eight thousand, three hundred sixty-nine".