1967773921 has 4 divisors (see below), whose sum is σ = 1968468912. Its totient is φ = 1967078932.

The previous prime is 1967773897. The next prime is 1967773937. The reversal of 1967773921 is 1293777691.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1967773921 - 2²⁹ = 1430903009 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1967773961) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 343231 + ... + 348916.

It is an arithmetic number, because the mean of its divisors is an integer number (492117228).

Almost surely, 2^1967773921 is an apocalyptic number.

It is an amenable number.

1967773921 is a deficient number, since it is larger than the sum of its proper divisors (694991).

1967773921 is an equidigital number, since it uses as much as digits as its factorization.

1967773921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 694990.

The product of its digits is 1000188, while the sum is 52.

The square root of 1967773921 is about 44359.5978453367. The cubic root of 1967773921 is about 1253.1173225243.

The spelling of 1967773921 in words is "one billion, nine hundred sixty-seven million, seven hundred seventy-three thousand, nine hundred twenty-one".