21001158415 has 8 divisors (see below), whose sum is σ = 25505021808. Its totient is φ = 16598505600.

The previous prime is 21001158407. The next prime is 21001158427. The reversal of 21001158415 is 51485110012.

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

It is not a de Polignac number, because 21001158415 - 2³ = 21001158407 is a prime.

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 (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 25302186 + ... + 25303015.

It is an arithmetic number, because the mean of its divisors is an integer number (3188127726).

Almost surely, 2^21001158415 is an apocalyptic number.

21001158415 is a deficient number, since it is larger than the sum of its proper divisors (4503863393).

21001158415 is an equidigital number, since it uses as much as digits as its factorization.

21001158415 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 50605289.

The product of its (nonzero) digits is 1600, while the sum is 28.

Adding to 21001158415 its reverse (51485110012), we get a palindrome (72486268427).

The spelling of 21001158415 in words is "twenty-one billion, one million, one hundred fifty-eight thousand, four hundred fifteen".