30616981 has 2 divisors, whose sum is σ = 30616982. Its totient is φ = 30616980.

The previous prime is 30616973. The next prime is 30616991. The reversal of 30616981 is 18961603.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 24900100 + 5716881 = 4990^2 + 2391^2 .

It is a cyclic number.

It is not a de Polignac number, because 30616981 - 2³ = 30616973 is a prime.

It is a super-2 number, since 2×30616981² = 1874799051108722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (30616931) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15308490 + 15308491.

It is an arithmetic number, because the mean of its divisors is an integer number (15308491).

Almost surely, 2^30616981 is an apocalyptic number.

It is an amenable number.

30616981 is a deficient number, since it is larger than the sum of its proper divisors (1).

30616981 is an equidigital number, since it uses as much as digits as its factorization.

30616981 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 7776, while the sum is 34.

The square root of 30616981 is about 5533.2613348730. The cubic root of 30616981 is about 312.8389274240.

The spelling of 30616981 in words is "thirty million, six hundred sixteen thousand, nine hundred eighty-one".