130031021 has 4 divisors (see below), whose sum is σ = 131181852. Its totient is φ = 128880192.

The previous prime is 130031017. The next prime is 130031023. The reversal of 130031021 is 120130031.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 120130031 = 7 ⋅17161433.

It can be written as a sum of positive squares in 2 ways, for example, as 23136100 + 106894921 = 4810^2 + 10339^2 .

It is a cyclic number.

It is not a de Polignac number, because 130031021 - 2² = 130031017 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 130030993 and 130031011.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (130031023) 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, 575246 + ... + 575471.

It is an arithmetic number, because the mean of its divisors is an integer number (32795463).

Almost surely, 2^130031021 is an apocalyptic number.

It is an amenable number.

130031021 is a deficient number, since it is larger than the sum of its proper divisors (1150831).

130031021 is a wasteful number, since it uses less digits than its factorization.

130031021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1150830.

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

The square root of 130031021 is about 11403.1145306885. The cubic root of 130031021 is about 506.6199925746.

Adding to 130031021 its reverse (120130031), we get a palindrome (250161052).

The spelling of 130031021 in words is "one hundred thirty million, thirty-one thousand, twenty-one".