661038336 has 216 divisors, whose sum is σ = 2307299904. Its totient is φ = 177684480.

The previous prime is 661038307. The next prime is 661038341. The reversal of 661038336 is 633830166.

661038336 is a `hidden beast` number, since 6 + 610 + 3 + 8 + 3 + 36 = 666.

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 661038336.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 272971 + ... + 275381.

It is an arithmetic number, because the mean of its divisors is an integer number (10681944).

Almost surely, 2^661038336 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 661038336, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1153649952).

661038336 is an abundant number, since it is smaller than the sum of its proper divisors (1646261568).

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

661038336 is a wasteful number, since it uses less digits than its factorization.

661038336 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2457 (or 2440 counting only the distinct ones).

The product of its (nonzero) digits is 46656, while the sum is 36.

The square root of 661038336 is about 25710.6658023475. The cubic root of 661038336 is about 871.1151139002.

The spelling of 661038336 in words is "six hundred sixty-one million, thirty-eight thousand, three hundred thirty-six".