6661501400 has 48 divisors (see below), whose sum is σ = 15536996640. Its totient is φ = 2656169600.

The previous prime is 6661501381. The next prime is 6661501411. The reversal of 6661501400 is 41051666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 10865 + ... + 115935.

It is an arithmetic number, because the mean of its divisors is an integer number (323687430).

Almost surely, 2^6661501400 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 6661501400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (7768498320).

6661501400 is an abundant number, since it is smaller than the sum of its proper divisors (8875495240).

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

6661501400 is a wasteful number, since it uses less digits than its factorization.

6661501400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 105404 (or 105395 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 29.

The square root of 6661501400 is about 81618.0212943196. The cubic root of 6661501400 is about 1881.5858619707.

The spelling of 6661501400 in words is "six billion, six hundred sixty-one million, five hundred one thousand, four hundred".