21554320142 has 32 divisors (see below), whose sum is σ = 34311803904. Its totient is φ = 10134432000.

The previous prime is 21554320127. The next prime is 21554320147. The reversal of 21554320142 is 24102345512.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21554320147) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 657767 + ... + 689757.

It is an arithmetic number, because the mean of its divisors is an integer number (1072243872).

Almost surely, 2^21554320142 is an apocalyptic number.

21554320142 is a deficient number, since it is larger than the sum of its proper divisors (12757483762).

21554320142 is a wasteful number, since it uses less digits than its factorization.

21554320142 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32264.

The product of its (nonzero) digits is 9600, while the sum is 29.

Adding to 21554320142 its reverse (24102345512), we get a palindrome (45656665654).

The spelling of 21554320142 in words is "twenty-one billion, five hundred fifty-four million, three hundred twenty thousand, one hundred forty-two".