1640016557 has 4 divisors (see below), whose sum is σ = 1641685920. Its totient is φ = 1638347196.

The previous prime is 1640016551. The next prime is 1640016563. The reversal of 1640016557 is 7556100461.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is an interprime number because it is at equal distance from previous prime (1640016551) and next prime (1640016563).

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1640016557 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 (1640016551) 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, 833207 + ... + 835172.

It is an arithmetic number, because the mean of its divisors is an integer number (410421480).

Almost surely, 2^1640016557 is an apocalyptic number.

It is an amenable number.

1640016557 is a deficient number, since it is larger than the sum of its proper divisors (1669363).

1640016557 is an equidigital number, since it uses as much as digits as its factorization.

1640016557 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1669362.

The product of its (nonzero) digits is 25200, while the sum is 35.

The square root of 1640016557 is about 40497.1178851039. The cubic root of 1640016557 is about 1179.2776765244.

The spelling of 1640016557 in words is "one billion, six hundred forty million, sixteen thousand, five hundred fifty-seven".