661909446 has 36 divisors (see below), whose sum is σ = 1576370796. Its totient is φ = 200577960.

The previous prime is 661909439. The next prime is 661909463. The reversal of 661909446 is 644909166.

It is a super-2 number, since 2×661909446² = 876248229408053832, which 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 17 ways as a sum of consecutive naturals, for example, 149776 + ... + 154131.

Almost surely, 2^661909446 is an apocalyptic number.

661909446 is a gapful number since it is divisible by the number (66) formed by its first and last digit.

661909446 is an abundant number, since it is smaller than the sum of its proper divisors (914461350).

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

661909446 is a wasteful number, since it uses less digits than its factorization.

661909446 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 303937 (or 303923 counting only the distinct ones).

The product of its (nonzero) digits is 279936, while the sum is 45.

The square root of 661909446 is about 25727.6008597770. The cubic root of 661909446 is about 871.4975949959.

The spelling of 661909446 in words is "six hundred sixty-one million, nine hundred nine thousand, four hundred forty-six".