315000021 has 32 divisors (see below), whose sum is σ = 524648448. Its totient is φ = 163941120.

The previous prime is 315000013. The next prime is 315000029. The reversal of 315000021 is 120000513.

It is an interprime number because it is at equal distance from previous prime (315000013) and next prime (315000029).

It is not a de Polignac number, because 315000021 - 2³ = 315000013 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 314999970 and 315000006.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (315000029) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3165 + ... + 25298.

It is an arithmetic number, because the mean of its divisors is an integer number (16395264).

Almost surely, 2^315000021 is an apocalyptic number.

315000021 is a gapful number since it is divisible by the number (31) formed by its first and last digit.

It is an amenable number.

315000021 is a deficient number, since it is larger than the sum of its proper divisors (209648427).

315000021 is a wasteful number, since it uses less digits than its factorization.

315000021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28521.

The product of its (nonzero) digits is 30, while the sum is 12.

The square root of 315000021 is about 17748.2399409068. The cubic root of 315000021 is about 680.4092267155.

Adding to 315000021 its reverse (120000513), we get a palindrome (435000534).

The spelling of 315000021 in words is "three hundred fifteen million, twenty-one", and thus it is an aban number.