21601757146 has 4 divisors (see below), whose sum is σ = 32402635722. Its totient is φ = 10800878572.

The previous prime is 21601757123. The next prime is 21601757147. The reversal of 21601757146 is 64175710612.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 19691105625 + 1910651521 = 140325^2 + 43711^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21601757099 and 21601757108.

It is not an unprimeable number, because it can be changed into a prime (21601757147) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5400439285 + ... + 5400439288.

Almost surely, 2^21601757146 is an apocalyptic number.

21601757146 is a deficient number, since it is larger than the sum of its proper divisors (10800878576).

21601757146 is a wasteful number, since it uses less digits than its factorization.

21601757146 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10800878575.

The product of its (nonzero) digits is 70560, while the sum is 40.

The spelling of 21601757146 in words is "twenty-one billion, six hundred one million, seven hundred fifty-seven thousand, one hundred forty-six".