20401837 has 8 divisors (see below), whose sum is σ = 21069176. Its totient is φ = 19740672.

The previous prime is 20401831. The next prime is 20401859. The reversal of 20401837 is 73810402.

It can be written as a sum of positive squares in 4 ways, for example, as 6007401 + 14394436 = 2451^2 + 3794^2 .

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

It is a 6-Lehmer number, since φ(20401837) divides (20401837-1)⁶.

It is a cyclic number.

It is not a de Polignac number, because 20401837 - 2⁷ = 20401709 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20401831) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5713 + ... + 8569.

It is an arithmetic number, because the mean of its divisors is an integer number (2633647).

Almost surely, 2^20401837 is an apocalyptic number.

20401837 is the 2857-th heptagonal number.

It is an amenable number.

20401837 is a deficient number, since it is larger than the sum of its proper divisors (667339).

20401837 is a wasteful number, since it uses less digits than its factorization.

20401837 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3087.

The product of its (nonzero) digits is 1344, while the sum is 25.

The square root of 20401837 is about 4516.8392709947. The cubic root of 20401837 is about 273.2476430112.

The spelling of 20401837 in words is "twenty million, four hundred one thousand, eight hundred thirty-seven".