1672764721 has 4 divisors (see below), whose sum is σ = 1672899172. Its totient is φ = 1672630272.

The previous prime is 1672764713. The next prime is 1672764761. The reversal of 1672764721 is 1274672761.

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 430977600 + 1241787121 = 20760^2 + 35239^2 .

It is a cyclic number.

It is not a de Polignac number, because 1672764721 - 2³ = 1672764713 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1672764761) 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, 46416 + ... + 74161.

It is an arithmetic number, because the mean of its divisors is an integer number (418224793).

Almost surely, 2^1672764721 is an apocalyptic number.

It is an amenable number.

1672764721 is a deficient number, since it is larger than the sum of its proper divisors (134451).

1672764721 is a wasteful number, since it uses less digits than its factorization.

1672764721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 134450.

The product of its digits is 197568, while the sum is 43.

The square root of 1672764721 is about 40899.4464632469. The cubic root of 1672764721 is about 1187.0753500802.

The spelling of 1672764721 in words is "one billion, six hundred seventy-two million, seven hundred sixty-four thousand, seven hundred twenty-one".