156999840 has 96 divisors (see below), whose sum is σ = 516087936. Its totient is φ = 40043520.

The previous prime is 156999797. The next prime is 156999847. The reversal of 156999840 is 48999651.

It is a tau number, because it is divible by the number of its divisors (96).

It is not an unprimeable number, because it can be changed into a prime (156999847) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3930 + ... + 18150.

It is an arithmetic number, because the mean of its divisors is an integer number (5375916).

Almost surely, 2^156999840 is an apocalyptic number.

156999840 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 156999840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (258043968).

156999840 is an abundant number, since it is smaller than the sum of its proper divisors (359088096).

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

156999840 is a wasteful number, since it uses less digits than its factorization.

156999840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14262 (or 14254 counting only the distinct ones).

The product of its (nonzero) digits is 699840, while the sum is 51.

The square root of 156999840 is about 12529.9577014450. The cubic root of 156999840 is about 539.4688879518.

The spelling of 156999840 in words is "one hundred fifty-six million, nine hundred ninety-nine thousand, eight hundred forty".