20211605545 has 8 divisors (see below), whose sum is σ = 24341487624. Its totient is φ = 16110910464.

The previous prime is 20211605539. The next prime is 20211605563. The reversal of 20211605545 is 54550611202.

It can be written as a sum of positive squares in 4 ways, for example, as 1036002969 + 19175602576 = 32187^2 + 138476^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 20211605545 - 2¹¹ = 20211603497 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7295224 + ... + 7297993.

It is an arithmetic number, because the mean of its divisors is an integer number (3042685953).

Almost surely, 2^20211605545 is an apocalyptic number.

It is an amenable number.

20211605545 is a deficient number, since it is larger than the sum of its proper divisors (4129882079).

20211605545 is a wasteful number, since it uses less digits than its factorization.

20211605545 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14593499.

The product of its (nonzero) digits is 12000, while the sum is 31.

The spelling of 20211605545 in words is "twenty billion, two hundred eleven million, six hundred five thousand, five hundred forty-five".