21213545032461 has 16 divisors (see below), whose sum is σ = 28296545064768. Its totient is φ = 14136455424000.

The previous prime is 21213545032423. The next prime is 21213545032483. The reversal of 21213545032461 is 16423054531212.

It is not a de Polignac number, because 21213545032461 - 2²³ = 21213536643853 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21213545036461) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 70115611 + ... + 70417511.

It is an arithmetic number, because the mean of its divisors is an integer number (1768534066548).

Almost surely, 2^{21213545032461} is an apocalyptic number.

It is an amenable number.

21213545032461 is a deficient number, since it is larger than the sum of its proper divisors (7083000032307).

21213545032461 is a wasteful number, since it uses less digits than its factorization.

21213545032461 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 311612.

The product of its (nonzero) digits is 172800, while the sum is 39.

Adding to 21213545032461 its reverse (16423054531212), we get a palindrome (37636599563673).

The spelling of 21213545032461 in words is "twenty-one trillion, two hundred thirteen billion, five hundred forty-five million, thirty-two thousand, four hundred sixty-one".