20978337 has 16 divisors (see below), whose sum is σ = 29712960. Its totient is φ = 13128192.

The previous prime is 20978317. The next prime is 20978359. The reversal of 20978337 is 73387902.

It is not a de Polignac number, because 20978337 - 2⁶ = 20978273 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20978295 and 20978304.

It is not an unprimeable number, because it can be changed into a prime (20978317) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4813 + ... + 8069.

It is an arithmetic number, because the mean of its divisors is an integer number (1857060).

Almost surely, 2^20978337 is an apocalyptic number.

It is an amenable number.

20978337 is a deficient number, since it is larger than the sum of its proper divisors (8734623).

20978337 is a wasteful number, since it uses less digits than its factorization.

20978337 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3392.

The product of its (nonzero) digits is 63504, while the sum is 39.

The square root of 20978337 is about 4580.2114580006. The cubic root of 20978337 is about 275.7975174200.

The spelling of 20978337 in words is "twenty million, nine hundred seventy-eight thousand, three hundred thirty-seven".