21217088260478 has 8 divisors (see below), whose sum is σ = 34718871699000. Its totient is φ = 9644131027480.

The previous prime is 21217088260441. The next prime is 21217088260603. The reversal of 21217088260478 is 87406288071212.

It is a happy number.

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

It is a super-3 number, since 3×21217088260478³ (a number of 41 digits) contains 333 as substring.

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, 482206551353 + ... + 482206551396.

It is an arithmetic number, because the mean of its divisors is an integer number (4339858962375).

Almost surely, 2^{21217088260478} is an apocalyptic number.

21217088260478 is a deficient number, since it is larger than the sum of its proper divisors (13501783438522).

21217088260478 is a wasteful number, since it uses less digits than its factorization.

21217088260478 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 964413102762.

The product of its (nonzero) digits is 4816896, while the sum is 56.

The spelling of 21217088260478 in words is "twenty-one trillion, two hundred seventeen billion, eighty-eight million, two hundred sixty thousand, four hundred seventy-eight".