21233077551 has 24 divisors (see below), whose sum is σ = 35061590304. Its totient is φ = 12129670080.

The previous prime is 21233077517. The next prime is 21233077573. The reversal of 21233077551 is 15577033212.

It is a happy number.

21233077551 is a `hidden beast` number, since 2 + 1 + 2 + 3 + 30 + 77 + 551 = 666.

It is not a de Polignac number, because 21233077551 - 2⁷ = 21233077423 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21233077501) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 178545 + ... + 272661.

It is an arithmetic number, because the mean of its divisors is an integer number (1460899596).

Almost surely, 2^21233077551 is an apocalyptic number.

21233077551 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

21233077551 is a deficient number, since it is larger than the sum of its proper divisors (13828512753).

21233077551 is a wasteful number, since it uses less digits than its factorization.

21233077551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 97711 (or 97708 counting only the distinct ones).

The product of its (nonzero) digits is 44100, while the sum is 36.

The spelling of 21233077551 in words is "twenty-one billion, two hundred thirty-three million, seventy-seven thousand, five hundred fifty-one".