21554103541 has 8 divisors (see below), whose sum is σ = 21838741400. Its totient is φ = 21270739968.

The previous prime is 21554103539. The next prime is 21554103583. The reversal of 21554103541 is 14530145512.

It can be written as a sum of positive squares in 4 ways, for example, as 4982948100 + 16571155441 = 70590^2 + 128729^2 .

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 21554103541 - 2¹ = 21554103539 is a prime.

It is a super-2 number, since 2×21554103541² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21554103041) 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, 284496 + ... + 352201.

It is an arithmetic number, because the mean of its divisors is an integer number (2729842675).

Almost surely, 2^21554103541 is an apocalyptic number.

It is an amenable number.

21554103541 is a deficient number, since it is larger than the sum of its proper divisors (284637859).

21554103541 is an equidigital number, since it uses as much as digits as its factorization.

21554103541 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 637143.

The product of its (nonzero) digits is 12000, while the sum is 31.

The spelling of 21554103541 in words is "twenty-one billion, five hundred fifty-four million, one hundred three thousand, five hundred forty-one".