21020194 has 32 divisors (see below), whose sum is σ = 37860480. Its totient is φ = 8646912.

The previous prime is 21020161. The next prime is 21020227. The reversal of 21020194 is 49102012.

It is an interprime number because it is at equal distance from previous prime (21020161) and next prime (21020227).

It is a Harshad number since it is a multiple of its sum of digits (19).

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, 7147 + ... + 9649.

It is an arithmetic number, because the mean of its divisors is an integer number (1183140).

Almost surely, 2^21020194 is an apocalyptic number.

21020194 is a deficient number, since it is larger than the sum of its proper divisors (16840286).

21020194 is a wasteful number, since it uses less digits than its factorization.

21020194 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2554.

The product of its (nonzero) digits is 144, while the sum is 19.

The square root of 21020194 is about 4584.7785115532. The cubic root of 21020194 is about 275.9808237745.

The spelling of 21020194 in words is "twenty-one million, twenty thousand, one hundred ninety-four".