21510198741 has 16 divisors (see below), whose sum is σ = 29314785024. Its totient is φ = 14023378944.

The previous prime is 21510198727. The next prime is 21510198833. The reversal of 21510198741 is 14789101512.

It is not a de Polignac number, because 21510198741 - 2¹⁰ = 21510197717 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21510198741.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21510198041) 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, 108921 + ... + 234273.

It is an arithmetic number, because the mean of its divisors is an integer number (1832174064).

Almost surely, 2^21510198741 is an apocalyptic number.

It is an amenable number.

21510198741 is a deficient number, since it is larger than the sum of its proper divisors (7804586283).

21510198741 is a wasteful number, since it uses less digits than its factorization.

21510198741 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 126620.

The product of its (nonzero) digits is 20160, while the sum is 39.

The spelling of 21510198741 in words is "twenty-one billion, five hundred ten million, one hundred ninety-eight thousand, seven hundred forty-one".