65121551220 has 48 divisors (see below), whose sum is σ = 198916740288. Its totient is φ = 15787042560.

The previous prime is 65121551203. The next prime is 65121551221. The reversal of 65121551220 is 2215512156.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65121551221) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 49333849 + ... + 49335168.

It is an arithmetic number, because the mean of its divisors is an integer number (4144098756).

Almost surely, 2^65121551220 is an apocalyptic number.

65121551220 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

65121551220 is an abundant number, since it is smaller than the sum of its proper divisors (133795189068).

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

65121551220 is a wasteful number, since it uses less digits than its factorization.

65121551220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 98669040 (or 98669038 counting only the distinct ones).

The product of its (nonzero) digits is 6000, while the sum is 30.

The spelling of 65121551220 in words is "sixty-five billion, one hundred twenty-one million, five hundred fifty-one thousand, two hundred twenty".