21006650442 has 64 divisors (see below), whose sum is σ = 42999828480. Its totient is φ = 6840193344.

The previous prime is 21006650429. The next prime is 21006650443. The reversal of 21006650442 is 24405660012.

It is not an unprimeable number, because it can be changed into a prime (21006650443) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 19044463 + ... + 19045565.

It is an arithmetic number, because the mean of its divisors is an integer number (671872320).

Almost surely, 2^21006650442 is an apocalyptic number.

21006650442 is an abundant number, since it is smaller than the sum of its proper divisors (21993178038).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21006650442 is a wasteful number, since it uses less digits than its factorization.

21006650442 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1587.

The product of its (nonzero) digits is 11520, while the sum is 30.

The spelling of 21006650442 in words is "twenty-one billion, six million, six hundred fifty thousand, four hundred forty-two".