20078237 has 4 divisors (see below), whose sum is σ = 20770620. Its totient is φ = 19385856.

The previous prime is 20078213. The next prime is 20078249. The reversal of 20078237 is 73287002.

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

It can be written as a sum of positive squares in 2 ways, for example, as 11978521 + 8099716 = 3461^2 + 2846^2 .

It is a cyclic number.

It is not a de Polignac number, because 20078237 - 2¹² = 20074141 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (29), and also a Moran number because the ratio is a prime number: 692353 = 20078237 / (2 + 0 + 0 + 7 + 8 + 2 + 3 + 7).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20078257) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 346148 + ... + 346205.

It is an arithmetic number, because the mean of its divisors is an integer number (5192655).

Almost surely, 2^20078237 is an apocalyptic number.

It is an amenable number.

20078237 is a deficient number, since it is larger than the sum of its proper divisors (692383).

20078237 is an equidigital number, since it uses as much as digits as its factorization.

20078237 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 692382.

The product of its (nonzero) digits is 4704, while the sum is 29.

The square root of 20078237 is about 4480.8745798114. The cubic root of 20078237 is about 271.7952476165.

The spelling of 20078237 in words is "twenty million, seventy-eight thousand, two hundred thirty-seven".