30529981 has 2 divisors, whose sum is σ = 30529982. Its totient is φ = 30529980.

The previous prime is 30529927. The next prime is 30529991. The reversal of 30529981 is 18992503.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 30525625 + 4356 = 5525^2 + 66^2 .

It is a cyclic number.

It is not a de Polignac number, because 30529981 - 2⁷ = 30529853 is a prime.

It is a super-2 number, since 2×30529981² = 1864159479720722, which contains 22 as substring.

It is equal to p_1888660 and since 30529981 and 1888660 have the same sum of digits, it is a Honaker prime.

It is a self number, because there is not a number n which added to its sum of digits gives 30529981.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (30529991) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15264990 + 15264991.

It is an arithmetic number, because the mean of its divisors is an integer number (15264991).

Almost surely, 2^30529981 is an apocalyptic number.

It is an amenable number.

30529981 is a deficient number, since it is larger than the sum of its proper divisors (1).

30529981 is an equidigital number, since it uses as much as digits as its factorization.

30529981 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 19440, while the sum is 37.

The square root of 30529981 is about 5525.3941940824. The cubic root of 30529981 is about 312.5423294127.

The spelling of 30529981 in words is "thirty million, five hundred twenty-nine thousand, nine hundred eighty-one".