21054042511 has 8 divisors (see below), whose sum is σ = 21085198848. Its totient is φ = 21022911000.

The previous prime is 21054042509. The next prime is 21054042517. The reversal of 21054042511 is 11524045012.

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 21054042511 - 2¹ = 21054042509 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21054042517) 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, 2256546 + ... + 2265856.

It is an arithmetic number, because the mean of its divisors is an integer number (2635649856).

Almost surely, 2^21054042511 is an apocalyptic number.

21054042511 is a deficient number, since it is larger than the sum of its proper divisors (31156337).

21054042511 is a wasteful number, since it uses less digits than its factorization.

21054042511 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12413.

The product of its (nonzero) digits is 1600, while the sum is 25.

Adding to 21054042511 its reverse (11524045012), we get a palindrome (32578087523).

The spelling of 21054042511 in words is "twenty-one billion, fifty-four million, forty-two thousand, five hundred eleven".