661207356 has 36 divisors (see below), whose sum is σ = 1687015512. Its totient is φ = 218341344.

The previous prime is 661207343. The next prime is 661207357. The reversal of 661207356 is 653702166.

661207356 is a `hidden beast` number, since 6 + 612 + 0 + 7 + 35 + 6 = 666.

It is a tau number, because it is divible by the number of its divisors (36).

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 661207356.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661207357) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 81975 + ... + 89678.

It is an arithmetic number, because the mean of its divisors is an integer number (46861542).

Almost surely, 2^661207356 is an apocalyptic number.

It is an amenable number.

661207356 is an abundant number, since it is smaller than the sum of its proper divisors (1025808156).

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

661207356 is a wasteful number, since it uses less digits than its factorization.

661207356 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 171770 (or 171765 counting only the distinct ones).

The product of its (nonzero) digits is 45360, while the sum is 36.

The square root of 661207356 is about 25713.9525549846. The cubic root of 661207356 is about 871.1893523225.

The spelling of 661207356 in words is "six hundred sixty-one million, two hundred seven thousand, three hundred fifty-six".