20978061 has 8 divisors (see below), whose sum is σ = 30122400. Its totient is φ = 12909552.

The previous prime is 20978021. The next prime is 20978077. The reversal of 20978061 is 16087902.

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

It is not a de Polignac number, because 20978061 - 2¹³ = 20969869 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20978011) 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, 268911 + ... + 268988.

It is an arithmetic number, because the mean of its divisors is an integer number (3765300).

Almost surely, 2^20978061 is an apocalyptic number.

It is an amenable number.

20978061 is a deficient number, since it is larger than the sum of its proper divisors (9144339).

20978061 is a wasteful number, since it uses less digits than its factorization.

20978061 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 537915.

The product of its (nonzero) digits is 6048, while the sum is 33.

The square root of 20978061 is about 4580.1813282882. The cubic root of 20978061 is about 275.7963079113.

The spelling of 20978061 in words is "twenty million, nine hundred seventy-eight thousand, sixty-one".