1640454516 has 72 divisors (see below), whose sum is σ = 4235868000. Its totient is φ = 535114944.

The previous prime is 1640454511. The next prime is 1640454521. The reversal of 1640454516 is 6154540461.

1640454516 is a `hidden beast` number, since 1 + 640 + 4 + 5 + 4 + 5 + 1 + 6 = 666.

It is an interprime number because it is at equal distance from previous prime (1640454511) and next prime (1640454521).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1640454511) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 951231 + ... + 952953.

It is an arithmetic number, because the mean of its divisors is an integer number (58831500).

Almost surely, 2^1640454516 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1640454516, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2117934000).

1640454516 is an abundant number, since it is smaller than the sum of its proper divisors (2595413484).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1640454516 is a wasteful number, since it uses less digits than its factorization.

1640454516 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2285 (or 2280 counting only the distinct ones).

The product of its (nonzero) digits is 57600, while the sum is 36.

The square root of 1640454516 is about 40502.5248101893. The cubic root of 1640454516 is about 1179.3826407705.

Adding to 1640454516 its reverse (6154540461), we get a palindrome (7794994977).

The spelling of 1640454516 in words is "one billion, six hundred forty million, four hundred fifty-four thousand, five hundred sixteen".