21365161337751 has 128 divisors (see below), whose sum is σ = 36782833950720. Its totient is φ = 10709411328000.

The previous prime is 21365161337743. The next prime is 21365161337753. The reversal of 21365161337751 is 15773316156312.

It is not a de Polignac number, because 21365161337751 - 2³ = 21365161337743 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21365161337694 and 21365161337703.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21365161337753) by changing a digit.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 1061718376 + ... + 1061738498.

It is an arithmetic number, because the mean of its divisors is an integer number (287365890240).

Almost surely, 2^{21365161337751} is an apocalyptic number.

21365161337751 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

21365161337751 is a deficient number, since it is larger than the sum of its proper divisors (15417672612969).

21365161337751 is a wasteful number, since it uses less digits than its factorization.

21365161337751 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21477.

The product of its digits is 2381400, while the sum is 51.

The spelling of 21365161337751 in words is "twenty-one trillion, three hundred sixty-five billion, one hundred sixty-one million, three hundred thirty-seven thousand, seven hundred fifty-one".