83661408 has 72 divisors (see below), whose sum is σ = 250450200. Its totient is φ = 26417664.

The previous prime is 83661407. The next prime is 83661497. The reversal of 83661408 is 80416638.

It is a happy number.

83661408 is a `hidden beast` number, since 8 + 36 + 614 + 0 + 8 = 666.

It is a tau number, because it is divible by the number of its divisors (72).

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 (83661407) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2173 + ... + 13116.

It is an arithmetic number, because the mean of its divisors is an integer number (3478475).

Almost surely, 2^83661408 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 83661408, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (125225100).

83661408 is an abundant number, since it is smaller than the sum of its proper divisors (166788792).

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

83661408 is a wasteful number, since it uses less digits than its factorization.

83661408 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15324 (or 15313 counting only the distinct ones).

The product of its (nonzero) digits is 27648, while the sum is 36.

The square root of 83661408 is about 9146.6610301246. The cubic root of 83661408 is about 437.3626810400.

The spelling of 83661408 in words is "eighty-three million, six hundred sixty-one thousand, four hundred eight".