21151052545 has 16 divisors (see below), whose sum is σ = 29159036928. Its totient is φ = 14427639360.

The previous prime is 21151052543. The next prime is 21151052557. The reversal of 21151052545 is 54525015112.

It is not a de Polignac number, because 21151052545 - 2¹ = 21151052543 is a prime.

It is a super-2 number, since 2×21151052545² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21151052543) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1575294 + ... + 1588663.

It is an arithmetic number, because the mean of its divisors is an integer number (1822439808).

Almost surely, 2^21151052545 is an apocalyptic number.

It is an amenable number.

21151052545 is a deficient number, since it is larger than the sum of its proper divisors (8007984383).

21151052545 is a wasteful number, since it uses less digits than its factorization.

21151052545 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3164160.

The product of its (nonzero) digits is 10000, while the sum is 31.

Adding to 21151052545 its reverse (54525015112), we get a palindrome (75676067657).

The spelling of 21151052545 in words is "twenty-one billion, one hundred fifty-one million, fifty-two thousand, five hundred forty-five".