30131021 has 8 divisors (see below), whose sum is σ = 32000184. Its totient is φ = 28272640.

The previous prime is 30130999. The next prime is 30131033. The reversal of 30131021 is 12013103.

It can be written as a sum of positive squares in 4 ways, for example, as 13402921 + 16728100 = 3661^2 + 4090^2 .

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 30131021 - 2⁶ = 30130957 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 30130993 and 30131011.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (30131041) 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, 3491 + ... + 8511.

It is an arithmetic number, because the mean of its divisors is an integer number (4000023).

Almost surely, 2^30131021 is an apocalyptic number.

It is an amenable number.

30131021 is a deficient number, since it is larger than the sum of its proper divisors (1869163).

30131021 is a wasteful number, since it uses less digits than its factorization.

30131021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5391.

The product of its (nonzero) digits is 18, while the sum is 11.

The square root of 30131021 is about 5489.1730706911. The cubic root of 30131021 is about 311.1749411219.

Adding to 30131021 its reverse (12013103), we get a palindrome (42144124).

It can be divided in two parts, 3013102 and 1, that added together give a palindrome (3013103).

The spelling of 30131021 in words is "thirty million, one hundred thirty-one thousand, twenty-one".