165858487440 has 40 divisors (see below), whose sum is σ = 514161311808. Its totient is φ = 44228929920.

The previous prime is 165858487427. The next prime is 165858487441. The reversal of 165858487440 is 44784858561.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (40).

It is a Harshad number since it is a multiple of its sum of digits (60).

It is not an unprimeable number, because it can be changed into a prime (165858487441) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 345538276 + ... + 345538755.

Almost surely, 2^165858487440 is an apocalyptic number.

165858487440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

165858487440 is an abundant number, since it is smaller than the sum of its proper divisors (348302824368).

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

165858487440 is a wasteful number, since it uses less digits than its factorization.

165858487440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 691077047 (or 691077041 counting only the distinct ones).

The product of its (nonzero) digits is 34406400, while the sum is 60.

The spelling of 165858487440 in words is "one hundred sixty-five billion, eight hundred fifty-eight million, four hundred eighty-seven thousand, four hundred forty".