21179653890 has 32 divisors (see below), whose sum is σ = 50906301120. Its totient is φ = 5639559744.

The previous prime is 21179653889. The next prime is 21179653909. The reversal of 21179653890 is 9835697112.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 501100 + ... + 541719.

It is an arithmetic number, because the mean of its divisors is an integer number (1590821910).

Almost surely, 2^21179653890 is an apocalyptic number.

21179653890 is an abundant number, since it is smaller than the sum of its proper divisors (29726647230).

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

21179653890 is a wasteful number, since it uses less digits than its factorization.

21179653890 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1043506.

The product of its (nonzero) digits is 816480, while the sum is 51.

The spelling of 21179653890 in words is "twenty-one billion, one hundred seventy-nine million, six hundred fifty-three thousand, eight hundred ninety".