43720820 has 48 divisors (see below), whose sum is σ = 107872128. Its totient is φ = 14674560.

The previous prime is 43720793. The next prime is 43720823. The reversal of 43720820 is 2802734.

43720820 = 69² + 70² + ... + 508².

It is a Harshad number since it is a multiple of its sum of digits (26).

It is a self number, because there is not a number n which added to its sum of digits gives 43720820.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (43720823) 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, 4784 + ... + 10503.

It is an arithmetic number, because the mean of its divisors is an integer number (2247336).

Almost surely, 2^43720820 is an apocalyptic number.

It is an amenable number.

43720820 is an abundant number, since it is smaller than the sum of its proper divisors (64151308).

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

43720820 is a wasteful number, since it uses less digits than its factorization.

43720820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15320 (or 15318 counting only the distinct ones).

The product of its (nonzero) digits is 2688, while the sum is 26.

The square root of 43720820 is about 6612.1721090728. The cubic root of 43720820 is about 352.2865800651.

The spelling of 43720820 in words is "forty-three million, seven hundred twenty thousand, eight hundred twenty".