20451561045 has 16 divisors (see below), whose sum is σ = 32735767680. Its totient is φ = 10903075904.

The previous prime is 20451561043. The next prime is 20451561071. The reversal of 20451561045 is 54016515402.

It is a cyclic number.

It is not a de Polignac number, because 20451561045 - 2¹ = 20451561043 is a prime.

It is a super-2 number, since 2×20451561045² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 20451560997 and 20451561015.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20451561043) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 238065 + ... + 312374.

It is an arithmetic number, because the mean of its divisors is an integer number (2045985480).

Almost surely, 2^20451561045 is an apocalyptic number.

It is an amenable number.

20451561045 is a deficient number, since it is larger than the sum of its proper divisors (12284206635).

20451561045 is a wasteful number, since it uses less digits than its factorization.

20451561045 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 552924.

The product of its (nonzero) digits is 24000, while the sum is 33.

The spelling of 20451561045 in words is "twenty billion, four hundred fifty-one million, five hundred sixty-one thousand, forty-five".