661252702512 has 40 divisors (see below), whose sum is σ = 1767140846640. Its totient is φ = 212816961280.

The previous prime is 661252702489. The next prime is 661252702519. The reversal of 661252702512 is 215207252166.

661252702512 is digitally balanced in base 2 and base 4, because in such bases it contains all the possibile digits an equal number of times.

It is a super-4 number, since 4×661252702512⁴ (a number of 48 digits) contains 4444 as substring. Note that it is a super-d number also for d = 2.

It is not an unprimeable number, because it can be changed into a prime (661252702519) 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, 237517539 + ... + 237520322.

It is an arithmetic number, because the mean of its divisors is an integer number (44178521166).

Almost surely, 2^661252702512 is an apocalyptic number.

It is an amenable number.

661252702512 is an abundant number, since it is smaller than the sum of its proper divisors (1105888144128).

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

661252702512 is a wasteful number, since it uses less digits than its factorization.

661252702512 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 475037901 (or 475037895 counting only the distinct ones).

The product of its (nonzero) digits is 100800, while the sum is 39.

Adding to 661252702512 its reverse (215207252166), we get a palindrome (876459954678).

The spelling of 661252702512 in words is "six hundred sixty-one billion, two hundred fifty-two million, seven hundred two thousand, five hundred twelve".