1651328813 has 4 divisors (see below), whose sum is σ = 1748465820. Its totient is φ = 1554191808.

The previous prime is 1651328807. The next prime is 1651328831. The reversal of 1651328813 is 3188231561.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 3188231561 = 17 ⋅187543033.

It can be written as a sum of positive squares in 2 ways, for example, as 705274249 + 946054564 = 26557^2 + 30758^2 .

It is a cyclic number.

It is not a de Polignac number, because 1651328813 - 2⁴ = 1651328797 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1651328113) 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, 48568478 + ... + 48568511.

It is an arithmetic number, because the mean of its divisors is an integer number (437116455).

Almost surely, 2^1651328813 is an apocalyptic number.

It is an amenable number.

1651328813 is a deficient number, since it is larger than the sum of its proper divisors (97137007).

1651328813 is an equidigital number, since it uses as much as digits as its factorization.

1651328813 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 97137006.

The product of its digits is 34560, while the sum is 38.

The square root of 1651328813 is about 40636.5452886930. The cubic root of 1651328813 is about 1181.9828800595.

The spelling of 1651328813 in words is "one billion, six hundred fifty-one million, three hundred twenty-eight thousand, eight hundred thirteen".