21365035210525 has 24 divisors (see below), whose sum is σ = 26538652031400. Its totient is φ = 17062369843200.

The previous prime is 21365035210471. The next prime is 21365035210637. The reversal of 21365035210525 is 52501253056312.

It can be written as a sum of positive squares in 12 ways, for example, as 14481480146116 + 6883555064409 = 3805454^2 + 2623653^2 .

It is not a de Polignac number, because 21365035210525 - 2¹³ = 21365035202333 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 34723761 + ... + 35333689.

It is an arithmetic number, because the mean of its divisors is an integer number (1105777167975).

Almost surely, 2^{21365035210525} is an apocalyptic number.

21365035210525 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21365035210525 is a deficient number, since it is larger than the sum of its proper divisors (5173616820875).

21365035210525 is a wasteful number, since it uses less digits than its factorization.

21365035210525 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 612369 (or 612364 counting only the distinct ones).

The product of its (nonzero) digits is 270000, while the sum is 40.

Adding to 21365035210525 its reverse (52501253056312), we get a palindrome (73866288266837).

The spelling of 21365035210525 in words is "twenty-one trillion, three hundred sixty-five billion, thirty-five million, two hundred ten thousand, five hundred twenty-five".