21554623165245 has 8 divisors (see below), whose sum is σ = 34487397064416. Its totient is φ = 11495799021456.

The previous prime is 21554623165241. The next prime is 21554623165279. The reversal of 21554623165245 is 54256132645512.

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

It is not a de Polignac number, because 21554623165245 - 2² = 21554623165241 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21554623165241) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 718487438827 + ... + 718487438856.

It is an arithmetic number, because the mean of its divisors is an integer number (4310924633052).

Almost surely, 2^{21554623165245} is an apocalyptic number.

It is an amenable number.

21554623165245 is a deficient number, since it is larger than the sum of its proper divisors (12932773899171).

21554623165245 is a wasteful number, since it uses less digits than its factorization.

21554623165245 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1436974877691.

The product of its digits is 8640000, while the sum is 51.

The spelling of 21554623165245 in words is "twenty-one trillion, five hundred fifty-four billion, six hundred twenty-three million, one hundred sixty-five thousand, two hundred forty-five".