661246255506 has 16 divisors (see below), whose sum is σ = 1322791702848. Its totient is φ = 220365553200.

The previous prime is 661246255487. The next prime is 661246255511. The reversal of 661246255506 is 605552642166.

It is a super-2 number, since 2×661246255506² (a number of 24 digits) contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12437590 + ... + 12490641.

It is an arithmetic number, because the mean of its divisors is an integer number (82674481428).

Almost surely, 2^661246255506 is an apocalyptic number.

661246255506 is an abundant number, since it is smaller than the sum of its proper divisors (661545447342).

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

661246255506 is a wasteful number, since it uses less digits than its factorization.

661246255506 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24932657.

The product of its (nonzero) digits is 2592000, while the sum is 48.

The spelling of 661246255506 in words is "six hundred sixty-one billion, two hundred forty-six million, two hundred fifty-five thousand, five hundred six".