21450007640009 has 16 divisors (see below), whose sum is σ = 23685981757200. Its totient is φ = 19298664791040.

The previous prime is 21450007640003. The next prime is 21450007640041. The reversal of 21450007640009 is 90004670005412.

It can be written as a sum of positive squares in 8 ways, for example, as 1306741624384 + 20143266015625 = 1143128^2 + 4488125^2 .

It is a cyclic number.

It is not a de Polignac number, because 21450007640009 - 2¹² = 21450007635913 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21450007640003) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 18622922 + ... + 19741155.

It is an arithmetic number, because the mean of its divisors is an integer number (1480373859825).

Almost surely, 2^{21450007640009} is an apocalyptic number.

It is an amenable number.

21450007640009 is a deficient number, since it is larger than the sum of its proper divisors (2235974117191).

21450007640009 is a wasteful number, since it uses less digits than its factorization.

21450007640009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38365180.

The product of its (nonzero) digits is 60480, while the sum is 38.

The spelling of 21450007640009 in words is "twenty-one trillion, four hundred fifty billion, seven million, six hundred forty thousand, nine".