21505340253452 has 24 divisors (see below), whose sum is σ = 41728693015632. Its totient is φ = 9614906222400.

The previous prime is 21505340253433. The next prime is 21505340253461. The reversal of 21505340253452 is 25435204350512.

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, 4006208243 + ... + 4006213610.

It is an arithmetic number, because the mean of its divisors is an integer number (1738695542318).

Almost surely, 2^{21505340253452} is an apocalyptic number.

21505340253452 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

21505340253452 is a deficient number, since it is larger than the sum of its proper divisors (20223352762180).

21505340253452 is a wasteful number, since it uses less digits than its factorization.

21505340253452 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8012421929 (or 8012421927 counting only the distinct ones).

The product of its (nonzero) digits is 720000, while the sum is 41.

The spelling of 21505340253452 in words is "twenty-one trillion, five hundred five billion, three hundred forty million, two hundred fifty-three thousand, four hundred fifty-two".