21043551120 has 40 divisors (see below), whose sum is σ = 65235009216. Its totient is φ = 5611613568.

The previous prime is 21043551101. The next prime is 21043551149. The reversal of 21043551120 is 2115534012.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (40).

It is a Harshad number since it is a multiple of its sum of digits (24).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 43840492 + ... + 43840971.

Almost surely, 2^21043551120 is an apocalyptic number.

21043551120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21043551120 is an abundant number, since it is smaller than the sum of its proper divisors (44191458096).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21043551120 is a wasteful number, since it uses less digits than its factorization.

21043551120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 87681479 (or 87681473 counting only the distinct ones).

The product of its (nonzero) digits is 1200, while the sum is 24.

The spelling of 21043551120 in words is "twenty-one billion, forty-three million, five hundred fifty-one thousand, one hundred twenty".