21540201052 has 24 divisors (see below), whose sum is σ = 38741431680. Its totient is φ = 10471631040.

The previous prime is 21540201041. The next prime is 21540201061. The reversal of 21540201052 is 25010204512.

It is a super-2 number, since 2×21540201052² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

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, 162402 + ... + 263542.

It is an arithmetic number, because the mean of its divisors is an integer number (1614226320).

Almost surely, 2^21540201052 is an apocalyptic number.

It is an amenable number.

21540201052 is a deficient number, since it is larger than the sum of its proper divisors (17201230628).

21540201052 is a wasteful number, since it uses less digits than its factorization.

21540201052 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 102621 (or 102619 counting only the distinct ones).

The product of its (nonzero) digits is 800, while the sum is 22.

Adding to 21540201052 its reverse (25010204512), we get a palindrome (46550405564).

The spelling of 21540201052 in words is "twenty-one billion, five hundred forty million, two hundred one thousand, fifty-two".