21661465732410 has 128 divisors (see below), whose sum is σ = 62370404352000. Its totient is φ = 4710264744960.

The previous prime is 21661465732391. The next prime is 21661465732429. The reversal of 21661465732410 is 1423756416612.

It is an interprime number because it is at equal distance from previous prime (21661465732391) and next prime (21661465732429).

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 21661465732410.

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, 27814335 + ... + 28582514.

It is an arithmetic number, because the mean of its divisors is an integer number (487268784000).

Almost surely, 2^{21661465732410} is an apocalyptic number.

21661465732410 is an abundant number, since it is smaller than the sum of its proper divisors (40708938619590).

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

21661465732410 is a wasteful number, since it uses less digits than its factorization.

21661465732410 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 56396956.

The product of its (nonzero) digits is 1451520, while the sum is 48.

The spelling of 21661465732410 in words is "twenty-one trillion, six hundred sixty-one billion, four hundred sixty-five million, seven hundred thirty-two thousand, four hundred ten".