21503545011 has 64 divisors (see below), whose sum is σ = 34902604800. Its totient is φ = 13004437248.

The previous prime is 21503545003. The next prime is 21503545031. The reversal of 21503545011 is 11054530512.

21503545011 is a `hidden beast` number, since 2 + 150 + 3 + 5 + 4 + 501 + 1 = 666.

It is not a de Polignac number, because 21503545011 - 2³ = 21503545003 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (21503545031) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 13380370 + ... + 13381976.

It is an arithmetic number, because the mean of its divisors is an integer number (545353200).

Almost surely, 2^21503545011 is an apocalyptic number.

21503545011 is a deficient number, since it is larger than the sum of its proper divisors (13399059789).

21503545011 is a wasteful number, since it uses less digits than its factorization.

21503545011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2265 (or 2259 counting only the distinct ones).

The product of its (nonzero) digits is 3000, while the sum is 27.

The spelling of 21503545011 in words is "twenty-one billion, five hundred three million, five hundred forty-five thousand, eleven".