21619374 has 16 divisors (see below), whose sum is σ = 49415808. Its totient is φ = 6176952.

The previous prime is 21619373. The next prime is 21619399. The reversal of 21619374 is 47391612.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21619373) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 257332 + ... + 257415.

It is an arithmetic number, because the mean of its divisors is an integer number (3088488).

Almost surely, 2^21619374 is an apocalyptic number.

21619374 is an abundant number, since it is smaller than the sum of its proper divisors (27796434).

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

21619374 is a wasteful number, since it uses less digits than its factorization.

21619374 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 514759.

The product of its digits is 9072, while the sum is 33.

The square root of 21619374 is about 4649.6638588182. The cubic root of 21619374 is about 278.5785700808.

The spelling of 21619374 in words is "twenty-one million, six hundred nineteen thousand, three hundred seventy-four".