20951530 has 16 divisors (see below), whose sum is σ = 37771560. Its totient is φ = 8367552.

The previous prime is 20951527. The next prime is 20951537. The reversal of 20951530 is 3515902.

It can be written as a sum of positive squares in 4 ways, for example, as 17480761 + 3470769 = 4181^2 + 1863^2 .

It is a junction number, because it is equal to n+sod(n) for n = 20951495 and 20951504.

It is not an unprimeable number, because it can be changed into a prime (20951537) 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, 7576 + ... + 9964.

Almost surely, 2^20951530 is an apocalyptic number.

20951530 is a deficient number, since it is larger than the sum of its proper divisors (16820030).

20951530 is a wasteful number, since it uses less digits than its factorization.

20951530 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3273.

The product of its (nonzero) digits is 1350, while the sum is 25.

The square root of 20951530 is about 4577.2841292627. The cubic root of 20951530 is about 275.6799921296.

The spelling of 20951530 in words is "twenty million, nine hundred fifty-one thousand, five hundred thirty".