21730406515 has 8 divisors (see below), whose sum is σ = 26712499968. Its totient is φ = 16960317120.

The previous prime is 21730406507. The next prime is 21730406543. The reversal of 21730406515 is 51560403712.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21730406515 - 2³ = 21730406507 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 53000787 + ... + 53001196.

It is an arithmetic number, because the mean of its divisors is an integer number (3339062496).

Almost surely, 2^21730406515 is an apocalyptic number.

21730406515 is a deficient number, since it is larger than the sum of its proper divisors (4982093453).

21730406515 is a wasteful number, since it uses less digits than its factorization.

21730406515 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 106002029.

The product of its (nonzero) digits is 25200, while the sum is 34.

The spelling of 21730406515 in words is "twenty-one billion, seven hundred thirty million, four hundred six thousand, five hundred fifteen".