30781961 has 8 divisors (see below), whose sum is σ = 35603904. Its totient is φ = 26066160.

The previous prime is 30781943. The next prime is 30781973. The reversal of 30781961 is 16918703.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 30781961 - 2⁶ = 30781897 is a prime.

It is not an unprimeable number, because it can be changed into a prime (30781901) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 25910 + ... + 27071.

It is an arithmetic number, because the mean of its divisors is an integer number (4450488).

Almost surely, 2^30781961 is an apocalyptic number.

It is an amenable number.

30781961 is a deficient number, since it is larger than the sum of its proper divisors (4821943).

30781961 is an equidigital number, since it uses as much as digits as its factorization.

30781961 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53071.

The product of its (nonzero) digits is 9072, while the sum is 35.

The square root of 30781961 is about 5548.1493310833. The cubic root of 30781961 is about 313.3998333529.

The spelling of 30781961 in words is "thirty million, seven hundred eighty-one thousand, nine hundred sixty-one".