661378041336 has 32 divisors (see below), whose sum is σ = 1653901695360. Its totient is φ = 220398468192.

The previous prime is 661378041281. The next prime is 661378041341. The reversal of 661378041336 is 633140873166.

It is a super-2 number, since 2×661378041336² (a number of 24 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3716170 + ... + 3890073.

It is an arithmetic number, because the mean of its divisors is an integer number (51684427980).

Almost surely, 2^661378041336 is an apocalyptic number.

It is an amenable number.

661378041336 is an abundant number, since it is smaller than the sum of its proper divisors (992523654024).

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

661378041336 is a wasteful number, since it uses less digits than its factorization.

661378041336 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7609875 (or 7609871 counting only the distinct ones).

The product of its (nonzero) digits is 1306368, while the sum is 48.

The spelling of 661378041336 in words is "six hundred sixty-one billion, three hundred seventy-eight million, forty-one thousand, three hundred thirty-six".