21232778053 has 8 divisors (see below), whose sum is σ = 21293227800. Its totient is φ = 21172359168.

The previous prime is 21232778051. The next prime is 21232778057. The reversal of 21232778053 is 35087723212.

It can be written as a sum of positive squares in 4 ways, for example, as 4870849 + 21227907204 = 2207^2 + 145698^2 .

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 21232778053 - 2¹ = 21232778051 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21232777997 and 21232778015.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21232778051) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2373493 + ... + 2382421.

It is an arithmetic number, because the mean of its divisors is an integer number (2661653475).

Almost surely, 2^21232778053 is an apocalyptic number.

It is an amenable number.

21232778053 is a deficient number, since it is larger than the sum of its proper divisors (60449747).

21232778053 is an equidigital number, since it uses as much as digits as its factorization.

21232778053 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15431.

The product of its (nonzero) digits is 141120, while the sum is 40.

The spelling of 21232778053 in words is "twenty-one billion, two hundred thirty-two million, seven hundred seventy-eight thousand, fifty-three".