21078654 has 16 divisors (see below), whose sum is σ = 43054848. Its totient is φ = 6876632.

The previous prime is 21078637. The next prime is 21078703. The reversal of 21078654 is 45687012.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 37092 + ... + 37655.

It is an arithmetic number, because the mean of its divisors is an integer number (2690928).

Almost surely, 2^21078654 is an apocalyptic number.

21078654 is an abundant number, since it is smaller than the sum of its proper divisors (21976194).

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

21078654 is a wasteful number, since it uses less digits than its factorization.

21078654 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 74799.

The product of its (nonzero) digits is 13440, while the sum is 33.

The square root of 21078654 is about 4591.1495292574. The cubic root of 21078654 is about 276.2364336137.

The spelling of 21078654 in words is "twenty-one million, seventy-eight thousand, six hundred fifty-four".