30027981 has 4 divisors (see below), whose sum is σ = 40037312. Its totient is φ = 20018652.

The previous prime is 30027973. The next prime is 30028003. The reversal of 30027981 is 18972003.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 30027981 - 2³ = 30027973 is a prime.

It is a super-2 number, since 2×30027981² = 1803359285872722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (30027901) 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, 5004661 + ... + 5004666.

It is an arithmetic number, because the mean of its divisors is an integer number (10009328).

Almost surely, 2^30027981 is an apocalyptic number.

It is an amenable number.

30027981 is a deficient number, since it is larger than the sum of its proper divisors (10009331).

30027981 is a wasteful number, since it uses less digits than its factorization.

30027981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10009330.

The product of its (nonzero) digits is 3024, while the sum is 30.

The square root of 30027981 is about 5479.7792838763. The cubic root of 30027981 is about 310.8198244354.

Adding to 30027981 its reverse (18972003), we get a palindrome (48999984).

The spelling of 30027981 in words is "thirty million, twenty-seven thousand, nine hundred eighty-one".