83661405 has 16 divisors (see below), whose sum is σ = 138177024. Its totient is φ = 43179840.

The previous prime is 83661367. The next prime is 83661407. The reversal of 83661405 is 50416638.

It is not a de Polignac number, because 83661405 - 2⁶ = 83661341 is a prime.

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 15 ways as a sum of consecutive naturals, for example, 89494 + ... + 90423.

It is an arithmetic number, because the mean of its divisors is an integer number (8636064).

Almost surely, 2^83661405 is an apocalyptic number.

It is an amenable number.

83661405 is a deficient number, since it is larger than the sum of its proper divisors (54515619).

83661405 is a wasteful number, since it uses less digits than its factorization.

83661405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 179956.

The product of its (nonzero) digits is 17280, while the sum is 33.

The square root of 83661405 is about 9146.6608661303. The cubic root of 83661405 is about 437.3626758122.

The spelling of 83661405 in words is "eighty-three million, six hundred sixty-one thousand, four hundred five".