21521034354 has 16 divisors (see below), whose sum is σ = 43356246048. Its totient is φ = 7121315232.

The previous prime is 21521034341. The next prime is 21521034371. The reversal of 21521034354 is 45343012512.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13089832 + ... + 13091475.

It is an arithmetic number, because the mean of its divisors is an integer number (2709765378).

Almost surely, 2^21521034354 is an apocalyptic number.

21521034354 is an abundant number, since it is smaller than the sum of its proper divisors (21835211694).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21521034354 is a wasteful number, since it uses less digits than its factorization.

21521034354 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26181449.

The product of its (nonzero) digits is 14400, while the sum is 30.

Adding to 21521034354 its reverse (45343012512), we get a palindrome (66864046866).

The spelling of 21521034354 in words is "twenty-one billion, five hundred twenty-one million, thirty-four thousand, three hundred fifty-four".