21428466 has 32 divisors (see below), whose sum is σ = 47770560. Its totient is φ = 6368256.

The previous prime is 21428461. The next prime is 21428489. The reversal of 21428466 is 66482412.

It is a super-2 number, since 2×21428466² = 918358310226312, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21428461) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3591 + ... + 7466.

It is an arithmetic number, because the mean of its divisors is an integer number (1492830).

Almost surely, 2^21428466 is an apocalyptic number.

21428466 is an abundant number, since it is smaller than the sum of its proper divisors (26342094).

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

21428466 is a wasteful number, since it uses less digits than its factorization.

21428466 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11098.

The product of its digits is 18432, while the sum is 33.

The square root of 21428466 is about 4629.0891112615. The cubic root of 21428466 is about 277.7561566223.

It can be divided in two parts, 214 and 28466, that added together give a triangular number (28680 = T₂₃₉).

The spelling of 21428466 in words is "twenty-one million, four hundred twenty-eight thousand, four hundred sixty-six".