21177572010 has 128 divisors (see below), whose sum is σ = 62245822464. Its totient is φ = 4500894720.

The previous prime is 21177571999. The next prime is 21177572021. The reversal of 21177572010 is 1027577112.

It is an interprime number because it is at equal distance from previous prime (21177571999) and next prime (21177572021).

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 260575 + ... + 332045.

It is an arithmetic number, because the mean of its divisors is an integer number (486295488).

Almost surely, 2^21177572010 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21177572010, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31122911232).

21177572010 is an abundant number, since it is smaller than the sum of its proper divisors (41068250454).

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

21177572010 is a wasteful number, since it uses less digits than its factorization.

21177572010 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 71588.

The product of its (nonzero) digits is 6860, while the sum is 33.

The spelling of 21177572010 in words is "twenty-one billion, one hundred seventy-seven million, five hundred seventy-two thousand, ten".