21006551510 has 16 divisors (see below), whose sum is σ = 43213477536. Its totient is φ = 7202246208.

The previous prime is 21006551507. The next prime is 21006551513. The reversal of 21006551510 is 1515560012.

It is an interprime number because it is at equal distance from previous prime (21006551507) and next prime (21006551513).

It is a self number, because there is not a number n which added to its sum of digits gives 21006551510.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21006551513) 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, 150046727 + ... + 150046866.

It is an arithmetic number, because the mean of its divisors is an integer number (2700842346).

Almost surely, 2^21006551510 is an apocalyptic number.

21006551510 is an abundant number, since it is smaller than the sum of its proper divisors (22206926026).

21006551510 is a wasteful number, since it uses less digits than its factorization.

21006551510 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 300093607.

The product of its (nonzero) digits is 1500, while the sum is 26.

The spelling of 21006551510 in words is "twenty-one billion, six million, five hundred fifty-one thousand, five hundred ten".