65215620 has 36 divisors (see below), whose sum is σ = 197821260. Its totient is φ = 17390784.

The previous prime is 65215597. The next prime is 65215627. The reversal of 65215620 is 2651256.

65215620 is a `hidden beast` number, since 652 + 1 + 5 + 6 + 2 + 0 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 34012224 + 31203396 = 5832^2 + 5586^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is not an unprimeable number, because it can be changed into a prime (65215627) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 180975 + ... + 181334.

It is an arithmetic number, because the mean of its divisors is an integer number (5495035).

Almost surely, 2^65215620 is an apocalyptic number.

65215620 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

65215620 is an abundant number, since it is smaller than the sum of its proper divisors (132605640).

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

65215620 is a wasteful number, since it uses less digits than its factorization.

65215620 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 362324 (or 362319 counting only the distinct ones).

The product of its (nonzero) digits is 3600, while the sum is 27.

The square root of 65215620 is about 8075.6188617344. The cubic root of 65215620 is about 402.5166743346.

Adding to 65215620 its reverse (2651256), we get a palindrome (67866876).

The spelling of 65215620 in words is "sixty-five million, two hundred fifteen thousand, six hundred twenty".