1640145515 has 4 divisors (see below), whose sum is σ = 1968174624. Its totient is φ = 1312116408.

The previous prime is 1640145469. The next prime is 1640145523. The reversal of 1640145515 is 5155410461.

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

It is a cyclic number.

It is not a de Polignac number, because 1640145515 - 2¹⁴ = 1640129131 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 164014547 + ... + 164014556.

It is an arithmetic number, because the mean of its divisors is an integer number (492043656).

Almost surely, 2^1640145515 is an apocalyptic number.

1640145515 is a deficient number, since it is larger than the sum of its proper divisors (328029109).

1640145515 is an equidigital number, since it uses as much as digits as its factorization.

1640145515 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 328029108.

The product of its (nonzero) digits is 12000, while the sum is 32.

The square root of 1640145515 is about 40498.7100411853. The cubic root of 1640145515 is about 1179.3085854206.

Adding to 1640145515 its reverse (5155410461), we get a palindrome (6795555976).

It can be divided in two parts, 16401 and 45515, that added together give a palindrome (61916).

The spelling of 1640145515 in words is "one billion, six hundred forty million, one hundred forty-five thousand, five hundred fifteen".