65181920 has 48 divisors (see below), whose sum is σ = 154677600. Its totient is φ = 25956864.

The previous prime is 65181917. The next prime is 65181929. The reversal of 65181920 is 2918156.

It is a Harshad number since it is a multiple of its sum of digits (32).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65181929) 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, 41306 + ... + 42854.

It is an arithmetic number, because the mean of its divisors is an integer number (3222450).

Almost surely, 2^65181920 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 65181920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (77338800).

65181920 is an abundant number, since it is smaller than the sum of its proper divisors (89495680).

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

65181920 is a wasteful number, since it uses less digits than its factorization.

65181920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1827 (or 1819 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 32.

The square root of 65181920 is about 8073.5320647162. The cubic root of 65181920 is about 402.4473292446.

The spelling of 65181920 in words is "sixty-five million, one hundred eighty-one thousand, nine hundred twenty".