Search a number
-
+
21720350550 = 2352211686267
BaseRepresentation
bin10100001110101000…
…100011111101010110
32002001201200010112210
4110032220203331112
5323440402204200
613551142254250
71366151635113
oct241650437526
962051603483
1021720350550
119236631938
124262127386
132081c2b042
1410a098790a
15871cde650
hex50ea23f56

21720350550 has 48 divisors (see below), whose sum is σ = 54121839552. Its totient is φ = 5764634400.

The previous prime is 21720350521. The next prime is 21720350551. The reversal of 21720350550 is 5505302712.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21720350551) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 311484 + ... + 374783.

It is an arithmetic number, because the mean of its divisors is an integer number (1127538324).

Almost surely, 221720350550 is an apocalyptic number.

21720350550 is an abundant number, since it is smaller than the sum of its proper divisors (32401489002).

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

21720350550 is a wasteful number, since it uses less digits than its factorization.

21720350550 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 686493 (or 686488 counting only the distinct ones).

The product of its (nonzero) digits is 10500, while the sum is 30.

The spelling of 21720350550 in words is "twenty-one billion, seven hundred twenty million, three hundred fifty thousand, five hundred fifty".

Divisors: 1 2 3 5 6 10 15 25 30 50 75 150 211 422 633 1055 1266 2110 3165 5275 6330 10550 15825 31650 686267 1372534 2058801 3431335 4117602 6862670 10294005 17156675 20588010 34313350 51470025 102940050 144802337 289604674 434407011 724011685 868814022 1448023370 2172035055 3620058425 4344070110 7240116850 10860175275 21720350550