1001640247 has 4 divisors (see below), whose sum is σ = 1001722680. Its totient is φ = 1001557816.

The previous prime is 1001640217. The next prime is 1001640293. The reversal of 1001640247 is 7420461001.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 7420461001 = 19 ⋅390550579.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1001640247 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 (1001640217) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 18997 + ... + 48622.

It is an arithmetic number, because the mean of its divisors is an integer number (250430670).

Almost surely, 2^1001640247 is an apocalyptic number.

1001640247 is a deficient number, since it is larger than the sum of its proper divisors (82433).

1001640247 is an equidigital number, since it uses as much as digits as its factorization.

1001640247 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 82432.

The product of its (nonzero) digits is 1344, while the sum is 25.

The square root of 1001640247 is about 31648.7005578428. The cubic root of 1001640247 is about 1000.5464503376.

The spelling of 1001640247 in words is "one billion, one million, six hundred forty thousand, two hundred forty-seven".