51021015 has 32 divisors (see below), whose sum is σ = 87284736. Its totient is φ = 25386240.

The previous prime is 51021011. The next prime is 51021037. The reversal of 51021015 is 51012015.

It is not a de Polignac number, because 51021015 - 2² = 51021011 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a junction number, because it is equal to n+sod(n) for n = 51020985 and 51021003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51021011) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 12342 + ... + 15948.

It is an arithmetic number, because the mean of its divisors is an integer number (2727648).

Almost surely, 2^51021015 is an apocalyptic number.

51021015 is a deficient number, since it is larger than the sum of its proper divisors (36263721).

51021015 is a wasteful number, since it uses less digits than its factorization.

51021015 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3679.

The product of its (nonzero) digits is 50, while the sum is 15.

The square root of 51021015 is about 7142.8996213023. The cubic root of 51021015 is about 370.8939063056.

The spelling of 51021015 in words is "fifty-one million, twenty-one thousand, fifteen".