661379634 has 16 divisors (see below), whose sum is σ = 1469732640. Its totient is φ = 220459860.

The previous prime is 661379581. The next prime is 661379671. The reversal of 661379634 is 436973166.

661379634 is a `hidden beast` number, since 6 + 6 + 1 + 3 + 7 + 9 + 634 = 666.

It is a self number, because there is not a number n which added to its sum of digits gives 661379634.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6123832 + ... + 6123939.

It is an arithmetic number, because the mean of its divisors is an integer number (91858290).

Almost surely, 2^661379634 is an apocalyptic number.

661379634 is an abundant number, since it is smaller than the sum of its proper divisors (808353006).

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

661379634 is a wasteful number, since it uses less digits than its factorization.

661379634 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12247782 (or 12247776 counting only the distinct ones).

The product of its digits is 489888, while the sum is 45.

The square root of 661379634 is about 25717.3022302107. The cubic root of 661379634 is about 871.2650087333.

The spelling of 661379634 in words is "six hundred sixty-one million, three hundred seventy-nine thousand, six hundred thirty-four".