1321664002 has 4 divisors (see below), whose sum is σ = 1982496006. Its totient is φ = 660832000.

The previous prime is 1321663957. The next prime is 1321664011. The reversal of 1321664002 is 2004661231.

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

It can be written as a sum of positive squares in only one way, i.e., 725278761 + 596385241 = 26931^2 + 24421^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 330415999 + ... + 330416002.

Almost surely, 2^1321664002 is an apocalyptic number.

1321664002 is a deficient number, since it is larger than the sum of its proper divisors (660832004).

1321664002 is an equidigital number, since it uses as much as digits as its factorization.

1321664002 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 660832003.

The product of its (nonzero) digits is 1728, while the sum is 25.

The square root of 1321664002 is about 36354.6971105523. The cubic root of 1321664002 is about 1097.4220628442.

The spelling of 1321664002 in words is "one billion, three hundred twenty-one million, six hundred sixty-four thousand, two".