20973540 has 48 divisors (see below), whose sum is σ = 67116672. Its totient is φ = 4793856.

The previous prime is 20973527. The next prime is 20973553. The reversal of 20973540 is 4537902.

It is an interprime number because it is at equal distance from previous prime (20973527) and next prime (20973553).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 20973498 and 20973507.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 24549 + ... + 25388.

It is an arithmetic number, because the mean of its divisors is an integer number (1398264).

Almost surely, 2^20973540 is an apocalyptic number.

20973540 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20973540 is an abundant number, since it is smaller than the sum of its proper divisors (46143132).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20973540 is a wasteful number, since it uses less digits than its factorization.

20973540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 49956 (or 49954 counting only the distinct ones).

The product of its (nonzero) digits is 7560, while the sum is 30.

The square root of 20973540 is about 4579.6877622825. The cubic root of 20973540 is about 275.7764941212.

The spelling of 20973540 in words is "twenty million, nine hundred seventy-three thousand, five hundred forty".