21554250351 has 8 divisors (see below), whose sum is σ = 30251579520. Its totient is φ = 13613210712.

The previous prime is 21554250349. The next prime is 21554250371. The reversal of 21554250351 is 15305245512.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21554250351 - 2¹ = 21554250349 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21554250331) 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, 189072315 + ... + 189072428.

It is an arithmetic number, because the mean of its divisors is an integer number (3781447440).

Almost surely, 2^21554250351 is an apocalyptic number.

21554250351 is a deficient number, since it is larger than the sum of its proper divisors (8697329169).

21554250351 is a wasteful number, since it uses less digits than its factorization.

21554250351 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 378144765.

The product of its (nonzero) digits is 30000, while the sum is 33.

Adding to 21554250351 its reverse (15305245512), we get a palindrome (36859495863).

The spelling of 21554250351 in words is "twenty-one billion, five hundred fifty-four million, two hundred fifty thousand, three hundred fifty-one".