20709554 has 4 divisors (see below), whose sum is σ = 31064334. Its totient is φ = 10354776.

The previous prime is 20709547. The next prime is 20709569. The reversal of 20709554 is 45590702.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 20025625 + 683929 = 4475^2 + 827^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 20709554.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5177387 + ... + 5177390.

Almost surely, 2^20709554 is an apocalyptic number.

20709554 is a deficient number, since it is larger than the sum of its proper divisors (10354780).

20709554 is a wasteful number, since it uses less digits than its factorization.

20709554 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10354779.

The product of its (nonzero) digits is 12600, while the sum is 32.

The square root of 20709554 is about 4550.7750988156. The cubic root of 20709554 is about 274.6145741088.

The spelling of 20709554 in words is "twenty million, seven hundred nine thousand, five hundred fifty-four".