1964340721 has 8 divisors (see below), whose sum is σ = 2275714304. Its totient is φ = 1660655520.

The previous prime is 1964340689. The next prime is 1964340733. The reversal of 1964340721 is 1270434691.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1964340721 - 2⁵ = 1964340689 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1964440721) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1921545 + ... + 1922566.

It is an arithmetic number, because the mean of its divisors is an integer number (284464288).

Almost surely, 2^1964340721 is an apocalyptic number.

It is an amenable number.

1964340721 is a deficient number, since it is larger than the sum of its proper divisors (311373583).

1964340721 is an equidigital number, since it uses as much as digits as its factorization.

1964340721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3844191.

The product of its (nonzero) digits is 36288, while the sum is 37.

The square root of 1964340721 is about 44320.8835764812. The cubic root of 1964340721 is about 1252.3881217408.

The spelling of 1964340721 in words is "one billion, nine hundred sixty-four million, three hundred forty thousand, seven hundred twenty-one".