661657477203 has 16 divisors (see below), whose sum is σ = 1006726092960. Its totient is φ = 429183227808.

The previous prime is 661657477183. The next prime is 661657477303. The reversal of 661657477203 is 302774756166.

It is a happy number.

661657477203 is a `hidden beast` number, since 6 + 6 + 165 + 7 + 477 + 2 + 0 + 3 = 666.

661657477203 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 not a de Polignac number, because 661657477203 - 2¹² = 661657473107 is a prime.

It is a super-3 number, since 3×661657477203³ (a number of 36 digits) contains 333 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 661657477203.

It is not an unprimeable number, because it can be changed into a prime (661657477303) 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, 331158900 + ... + 331160897.

It is an arithmetic number, because the mean of its divisors is an integer number (62920380810).

Almost surely, 2^661657477203 is an apocalyptic number.

661657477203 is a deficient number, since it is larger than the sum of its proper divisors (345068615757).

661657477203 is a wasteful number, since it uses less digits than its factorization.

661657477203 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 662319843 (or 662319837 counting only the distinct ones).

The product of its (nonzero) digits is 8890560, while the sum is 54.

The spelling of 661657477203 in words is "six hundred sixty-one billion, six hundred fifty-seven million, four hundred seventy-seven thousand, two hundred three".