1640295947 has 2 divisors, whose sum is σ = 1640295948. Its totient is φ = 1640295946.

The previous prime is 1640295929. The next prime is 1640295953. The reversal of 1640295947 is 7495920461.

It is a strong prime.

It is an emirp because it is prime and its reverse (7495920461) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1640295947 - 2⁸ = 1640295691 is a prime.

It is not a weakly prime, because it can be changed into another prime (1640295997) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 820147973 + 820147974.

It is an arithmetic number, because the mean of its divisors is an integer number (820147974).

Almost surely, 2^1640295947 is an apocalyptic number.

1640295947 is a deficient number, since it is larger than the sum of its proper divisors (1).

1640295947 is an equidigital number, since it uses as much as digits as its factorization.

1640295947 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 544320, while the sum is 47.

The square root of 1640295947 is about 40500.5672429412. The cubic root of 1640295947 is about 1179.3446391983.

The spelling of 1640295947 in words is "one billion, six hundred forty million, two hundred ninety-five thousand, nine hundred forty-seven".