21005140421552 has 40 divisors (see below), whose sum is σ = 46752374028576. Its totient is φ = 8955559489536.

The previous prime is 21005140421537. The next prime is 21005140421633. The reversal of 21005140421552 is 25512404150012.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 485848583 + ... + 485891814.

Almost surely, 2^{21005140421552} is an apocalyptic number.

It is an amenable number.

21005140421552 is an abundant number, since it is smaller than the sum of its proper divisors (25747233607024).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21005140421552 is a wasteful number, since it uses less digits than its factorization.

21005140421552 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 971740605 (or 971740599 counting only the distinct ones).

The product of its (nonzero) digits is 16000, while the sum is 32.

Adding to 21005140421552 its reverse (25512404150012), we get a palindrome (46517544571564).

The spelling of 21005140421552 in words is "twenty-one trillion, five billion, one hundred forty million, four hundred twenty-one thousand, five hundred fifty-two".