21019076 has 12 divisors (see below), whose sum is σ = 39612972. Its totient is φ = 9701088.

The previous prime is 21019069. The next prime is 21019127. The reversal of 21019076 is 67091012.

It can be written as a sum of positive squares in 2 ways, for example, as 948676 + 20070400 = 974^2 + 4480^2 .

It is a Harshad number since it is a multiple of its sum of digits (26).

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 202055 + ... + 202158.

It is an arithmetic number, because the mean of its divisors is an integer number (3301081).

Almost surely, 2^21019076 is an apocalyptic number.

21019076 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is an amenable number.

21019076 is a deficient number, since it is larger than the sum of its proper divisors (18593896).

21019076 is a wasteful number, since it uses less digits than its factorization.

21019076 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 404230 (or 404228 counting only the distinct ones).

The product of its (nonzero) digits is 756, while the sum is 26.

The square root of 21019076 is about 4584.6565847400. The cubic root of 21019076 is about 275.9759308283.

The spelling of 21019076 in words is "twenty-one million, nineteen thousand, seventy-six".