6616040400 has 90 divisors (see below), whose sum is σ = 22959510470. Its totient is φ = 1764276480.

The previous prime is 6616040393. The next prime is 6616040401. The reversal of 6616040400 is 40406166.

6616040400 is a `hidden beast` number, since 6 + 616 + 0 + 4 + 0 + 40 + 0 = 666.

It can be written as a sum of positive squares in 3 ways, for example, as 2186871696 + 4429168704 = 46764^2 + 66552^2 .

It is a tau number, because it is divible by the number of its divisors (90).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6616040401) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 915295 + ... + 922494.

Almost surely, 2^6616040400 is an apocalyptic number.

6616040400 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

6616040400 is an abundant number, since it is smaller than the sum of its proper divisors (16343470070).

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

6616040400 is a wasteful number, since it uses less digits than its factorization.

6616040400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1837813 (or 1837799 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 27.

The square root of 6616040400 is about 81339.0459742429. The cubic root of 6616040400 is about 1877.2958330663.

Adding to 6616040400 its reverse (40406166), we get a palindrome (6656446566).

The spelling of 6616040400 in words is "six billion, six hundred sixteen million, forty thousand, four hundred".