21055000145 has 8 divisors (see below), whose sum is σ = 25396913256. Its totient is φ = 16756724736.

The previous prime is 21055000097. The next prime is 21055000159. The reversal of 21055000145 is 54100055012.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 340882369 + 20714117776 = 18463^2 + 143924^2 .

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 21055000145 - 2³⁰ = 19981258321 is a prime.

It is a super-2 number, since 2×21055000145² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21055000145.

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, 10908362 + ... + 10910291.

It is an arithmetic number, because the mean of its divisors is an integer number (3174614157).

Almost surely, 2^21055000145 is an apocalyptic number.

It is an amenable number.

21055000145 is a deficient number, since it is larger than the sum of its proper divisors (4341913111).

21055000145 is a wasteful number, since it uses less digits than its factorization.

21055000145 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21818851.

The product of its (nonzero) digits is 1000, while the sum is 23.

Adding to 21055000145 its reverse (54100055012), we get a palindrome (75155055157).

The spelling of 21055000145 in words is "twenty-one billion, fifty-five million, one hundred forty-five", and thus it is an aban number.