65981220 has 24 divisors (see below), whose sum is σ = 184747584. Its totient is φ = 17594976.

The previous prime is 65981207. The next prime is 65981257. The reversal of 65981220 is 2218956.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 549784 + ... + 549903.

It is an arithmetic number, because the mean of its divisors is an integer number (7697816).

Almost surely, 2^65981220 is an apocalyptic number.

65981220 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

65981220 is an abundant number, since it is smaller than the sum of its proper divisors (118766364).

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

65981220 is a wasteful number, since it uses less digits than its factorization.

65981220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1099699 (or 1099697 counting only the distinct ones).

The product of its (nonzero) digits is 8640, while the sum is 33.

The square root of 65981220 is about 8122.8824933025. The cubic root of 65981220 is about 404.0856678768.

The spelling of 65981220 in words is "sixty-five million, nine hundred eighty-one thousand, two hundred twenty".