21515445525134 has 8 divisors (see below), whose sum is σ = 35207092677528. Its totient is φ = 9779747965960.

The previous prime is 21515445525121. The next prime is 21515445525143. The reversal of 21515445525134 is 43152554451512.

It is a happy number.

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

It is a super-2 number, since 2×21515445525134² (a number of 27 digits) contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 488987398277 + ... + 488987398320.

It is an arithmetic number, because the mean of its divisors is an integer number (4400886584691).

Almost surely, 2^{21515445525134} is an apocalyptic number.

21515445525134 is a deficient number, since it is larger than the sum of its proper divisors (13691647152394).

21515445525134 is a wasteful number, since it uses less digits than its factorization.

21515445525134 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 977974796610.

The product of its digits is 2400000, while the sum is 47.

Adding to 21515445525134 its reverse (43152554451512), we get a palindrome (64667999976646).

The spelling of 21515445525134 in words is "twenty-one trillion, five hundred fifteen billion, four hundred forty-five million, five hundred twenty-five thousand, one hundred thirty-four".