21651404545 has 8 divisors (see below), whose sum is σ = 27111324096. Its totient is φ = 16568031216.

The previous prime is 21651404519. The next prime is 21651404557. The reversal of 21651404545 is 54540415612.

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

It is a cyclic number.

It is not a de Polignac number, because 21651404545 - 2⁷ = 21651404417 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 94136427 + ... + 94136656.

It is an arithmetic number, because the mean of its divisors is an integer number (3388915512).

Almost surely, 2^21651404545 is an apocalyptic number.

It is an amenable number.

21651404545 is a deficient number, since it is larger than the sum of its proper divisors (5459919551).

21651404545 is a wasteful number, since it uses less digits than its factorization.

21651404545 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 188273111.

The product of its (nonzero) digits is 96000, while the sum is 37.

The spelling of 21651404545 in words is "twenty-one billion, six hundred fifty-one million, four hundred four thousand, five hundred forty-five".