315545021 has 4 divisors (see below), whose sum is σ = 344230944. Its totient is φ = 286859100.

The previous prime is 315545011. The next prime is 315545029. The reversal of 315545021 is 120545513.

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, and also an emirpimes, since its reverse is a distinct semiprime: 120545513 = 11 ⋅10958683.

It is not a de Polignac number, because 315545021 - 2²² = 311350717 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (315545029) 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, 14342945 + ... + 14342966.

It is an arithmetic number, because the mean of its divisors is an integer number (86057736).

Almost surely, 2^315545021 is an apocalyptic number.

It is an amenable number.

315545021 is a deficient number, since it is larger than the sum of its proper divisors (28685923).

315545021 is a wasteful number, since it uses less digits than its factorization.

315545021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28685922.

The product of its (nonzero) digits is 3000, while the sum is 26.

The square root of 315545021 is about 17763.5869407054. The cubic root of 315545021 is about 680.8014059201.

The spelling of 315545021 in words is "three hundred fifteen million, five hundred forty-five thousand, twenty-one".