30961661 has 4 divisors (see below), whose sum is σ = 31235772. Its totient is φ = 30687552.

The previous prime is 30961643. The next prime is 30961663. The reversal of 30961661 is 16616903.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 11689561 + 19272100 = 3419^2 + 4390^2 .

It is a cyclic number.

It is not a de Polignac number, because 30961661 - 2⁶ = 30961597 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 (30961663) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 136886 + ... + 137111.

It is an arithmetic number, because the mean of its divisors is an integer number (7808943).

Almost surely, 2^30961661 is an apocalyptic number.

It is an amenable number.

30961661 is a deficient number, since it is larger than the sum of its proper divisors (274111).

30961661 is a wasteful number, since it uses less digits than its factorization.

30961661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 274110.

The product of its (nonzero) digits is 5832, while the sum is 32.

The square root of 30961661 is about 5564.3203538258. The cubic root of 30961661 is about 314.0085092424.

The spelling of 30961661 in words is "thirty million, nine hundred sixty-one thousand, six hundred sixty-one".