21755421445442 has 8 divisors (see below), whose sum is σ = 33248851643196. Its totient is φ = 10672470897712.

The previous prime is 21755421445423. The next prime is 21755421445469. The reversal of 21755421445442 is 24454412455712.

It can be written as a sum of positive squares in 2 ways, for example, as 20587009618681 + 1168411826761 = 4537291^2 + 1080931^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-3 number, since 3×21755421445442³ (a number of 41 digits) contains 333 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 102619912373 + ... + 102619912584.

Almost surely, 2^{21755421445442} is an apocalyptic number.

21755421445442 is a deficient number, since it is larger than the sum of its proper divisors (11493430197754).

21755421445442 is a wasteful number, since it uses less digits than its factorization.

21755421445442 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 205239825012.

The product of its digits is 7168000, while the sum is 50.

The spelling of 21755421445442 in words is "twenty-one trillion, seven hundred fifty-five billion, four hundred twenty-one million, four hundred forty-five thousand, four hundred forty-two".