20001531215 has 8 divisors (see below), whose sum is σ = 24057528768. Its totient is φ = 15964097440.

The previous prime is 20001531191. The next prime is 20001531223. The reversal of 20001531215 is 51213510002.

It is a happy number.

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

It is a de Polignac number, because none of the positive numbers 2^k-20001531215 is a prime.

It is a super-2 number, since 2×20001531215² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4638572 + ... + 4642881.

It is an arithmetic number, because the mean of its divisors is an integer number (3007191096).

Almost surely, 2^20001531215 is an apocalyptic number.

20001531215 is a deficient number, since it is larger than the sum of its proper divisors (4055997553).

20001531215 is an equidigital number, since it uses as much as digits as its factorization.

20001531215 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9281889.

The product of its (nonzero) digits is 300, while the sum is 20.

The spelling of 20001531215 in words is "twenty billion, one million, five hundred thirty-one thousand, two hundred fifteen".