66021215252 has 6 divisors (see below), whose sum is σ = 115537126698. Its totient is φ = 33010607624.

The previous prime is 66021215243. The next prime is 66021215279. The reversal of 66021215252 is 25251212066.

It can be written as a sum of positive squares in only one way, i.e., 48825089296 + 17196125956 = 220964^2 + 131134^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8252651903 + ... + 8252651910.

It is an arithmetic number, because the mean of its divisors is an integer number (19256187783).

Almost surely, 2^66021215252 is an apocalyptic number.

It is an amenable number.

66021215252 is a deficient number, since it is larger than the sum of its proper divisors (49515911446).

66021215252 is a wasteful number, since it uses less digits than its factorization.

66021215252 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16505303817 (or 16505303815 counting only the distinct ones).

The product of its (nonzero) digits is 14400, while the sum is 32.

The spelling of 66021215252 in words is "sixty-six billion, twenty-one million, two hundred fifteen thousand, two hundred fifty-two".