30781361 has 4 divisors (see below), whose sum is σ = 33149172. Its totient is φ = 28413552.

The previous prime is 30781351. The next prime is 30781379. The reversal of 30781361 is 16318703.

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 19009600 + 11771761 = 4360^2 + 3431^2 .

It is a cyclic number.

It is not a de Polignac number, because 30781361 - 2¹⁴ = 30764977 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (30781321) 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, 1183886 + ... + 1183911.

It is an arithmetic number, because the mean of its divisors is an integer number (8287293).

Almost surely, 2^30781361 is an apocalyptic number.

It is an amenable number.

30781361 is a deficient number, since it is larger than the sum of its proper divisors (2367811).

30781361 is a wasteful number, since it uses less digits than its factorization.

30781361 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2367810.

The product of its (nonzero) digits is 3024, while the sum is 29.

The square root of 30781361 is about 5548.0952587352. The cubic root of 30781361 is about 313.3977970832.

The spelling of 30781361 in words is "thirty million, seven hundred eighty-one thousand, three hundred sixty-one".