661673349 has 6 divisors (see below), whose sum is σ = 955750406. Its totient is φ = 441115560.

The previous prime is 661673333. The next prime is 661673351. The reversal of 661673349 is 943376166.

It can be written as a sum of positive squares in only one way, i.e., 591365124 + 70308225 = 24318^2 + 8385^2 .

It is not a de Polignac number, because 661673349 - 2⁴ = 661673333 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661673249) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 36759622 + ... + 36759639.

Almost surely, 2^661673349 is an apocalyptic number.

It is an amenable number.

661673349 is a deficient number, since it is larger than the sum of its proper divisors (294077057).

661673349 is a wasteful number, since it uses less digits than its factorization.

661673349 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 73519267 (or 73519264 counting only the distinct ones).

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

The square root of 661673349 is about 25723.0120514686. The cubic root of 661673349 is about 871.3939642865.

The spelling of 661673349 in words is "six hundred sixty-one million, six hundred seventy-three thousand, three hundred forty-nine".