20751029 has 4 divisors (see below), whose sum is σ = 22347276. Its totient is φ = 19154784.

The previous prime is 20751023. The next prime is 20751047. The reversal of 20751029 is 92015702.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 92015702 = 2 ⋅46007851.

It can be written as a sum of positive squares in 2 ways, for example, as 1188100 + 19562929 = 1090^2 + 4423^2 .

It is a cyclic number.

It is not a de Polignac number, because 20751029 - 2¹² = 20746933 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 20750989 and 20751007.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20751023) 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 3 ways as a sum of consecutive naturals, for example, 798104 + ... + 798129.

It is an arithmetic number, because the mean of its divisors is an integer number (5586819).

Almost surely, 2^20751029 is an apocalyptic number.

It is an amenable number.

20751029 is a deficient number, since it is larger than the sum of its proper divisors (1596247).

20751029 is a wasteful number, since it uses less digits than its factorization.

20751029 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1596246.

The product of its (nonzero) digits is 1260, while the sum is 26.

The square root of 20751029 is about 4555.3297355954. The cubic root of 20751029 is about 274.7977752949.

The spelling of 20751029 in words is "twenty million, seven hundred fifty-one thousand, twenty-nine".