20980156 has 12 divisors (see below), whose sum is σ = 37408392. Its totient is φ = 10292048.

The previous prime is 20980153. The next prime is 20980177. The reversal of 20980156 is 65108902.

It is a super-4 number, since 4×20980156⁴ (a number of 30 digits) contains 4444 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20980153) 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, 49270 + ... + 49693.

It is an arithmetic number, because the mean of its divisors is an integer number (3117366).

Almost surely, 2^20980156 is an apocalyptic number.

It is an amenable number.

20980156 is a deficient number, since it is larger than the sum of its proper divisors (16428236).

20980156 is a wasteful number, since it uses less digits than its factorization.

20980156 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 99020 (or 99018 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 31.

The square root of 20980156 is about 4580.4100253143. The cubic root of 20980156 is about 275.8054885188.

The spelling of 20980156 in words is "twenty million, nine hundred eighty thousand, one hundred fifty-six".