1921946465 has 4 divisors (see below), whose sum is σ = 2306335764. Its totient is φ = 1537557168.

The previous prime is 1921946443. The next prime is 1921946479. The reversal of 1921946465 is 5646491291.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 796142656 + 1125803809 = 28216^2 + 33553^2 .

It is a cyclic number.

It is not a de Polignac number, because 1921946465 - 2¹⁸ = 1921684321 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 192194642 + ... + 192194651.

It is an arithmetic number, because the mean of its divisors is an integer number (576583941).

Almost surely, 2^1921946465 is an apocalyptic number.

It is an amenable number.

1921946465 is a deficient number, since it is larger than the sum of its proper divisors (384389299).

1921946465 is an equidigital number, since it uses as much as digits as its factorization.

1921946465 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 384389298.

The product of its digits is 466560, while the sum is 47.

The square root of 1921946465 is about 43840.0098654186. The cubic root of 1921946465 is about 1243.3128688150.

The spelling of 1921946465 in words is "one billion, nine hundred twenty-one million, nine hundred forty-six thousand, four hundred sixty-five".