21443851455 has 32 divisors (see below), whose sum is σ = 37168098240. Its totient is φ = 10556956800.

The previous prime is 21443851399. The next prime is 21443851469. The reversal of 21443851455 is 55415834412.

It is not a de Polignac number, because 21443851455 - 2¹⁷ = 21443720383 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 292396 + ... + 358305.

It is an arithmetic number, because the mean of its divisors is an integer number (1161503070).

Almost surely, 2^21443851455 is an apocalyptic number.

21443851455 is a deficient number, since it is larger than the sum of its proper divisors (15724246785).

21443851455 is an equidigital number, since it uses as much as digits as its factorization.

21443851455 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 650748 (or 650722 counting only the distinct ones).

The product of its digits is 384000, while the sum is 42.

The spelling of 21443851455 in words is "twenty-one billion, four hundred forty-three million, eight hundred fifty-one thousand, four hundred fifty-five".