21356755442 has 8 divisors (see below), whose sum is σ = 34947418032. Its totient is φ = 9707616100.

The previous prime is 21356755439. The next prime is 21356755451. The reversal of 21356755442 is 24455765312.

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

It is a super-2 number, since 2×21356755442² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21356755393 and 21356755402.

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, 485380784 + ... + 485380827.

It is an arithmetic number, because the mean of its divisors is an integer number (4368427254).

Almost surely, 2^21356755442 is an apocalyptic number.

21356755442 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

21356755442 is a deficient number, since it is larger than the sum of its proper divisors (13590662590).

21356755442 is a wasteful number, since it uses less digits than its factorization.

21356755442 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 970761624.

The product of its digits is 1008000, while the sum is 44.

The spelling of 21356755442 in words is "twenty-one billion, three hundred fifty-six million, seven hundred fifty-five thousand, four hundred forty-two".