1640456435 has 4 divisors (see below), whose sum is σ = 1968547728. Its totient is φ = 1312365144.

The previous prime is 1640456413. The next prime is 1640456437. The reversal of 1640456435 is 5346540461.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1640456435 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1640456437) 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, 164045639 + ... + 164045648.

It is an arithmetic number, because the mean of its divisors is an integer number (492136932).

Almost surely, 2^1640456435 is an apocalyptic number.

1640456435 is a deficient number, since it is larger than the sum of its proper divisors (328091293).

1640456435 is an equidigital number, since it uses as much as digits as its factorization.

1640456435 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 328091292.

The product of its (nonzero) digits is 172800, while the sum is 38.

The square root of 1640456435 is about 40502.5485000635. The cubic root of 1640456435 is about 1179.3831006500.

Adding to 1640456435 its reverse (5346540461), we get a palindrome (6986996896).

The spelling of 1640456435 in words is "one billion, six hundred forty million, four hundred fifty-six thousand, four hundred thirty-five".