21373429 has 8 divisors (see below), whose sum is σ = 26647488. Its totient is φ = 16654560.

The previous prime is 21373411. The next prime is 21373447. The reversal of 21373429 is 92437312.

It is an interprime number because it is at equal distance from previous prime (21373411) and next prime (21373447).

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21373429 - 2⁵ = 21373397 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21373429.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21373409) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 138712 + ... + 138865.

It is an arithmetic number, because the mean of its divisors is an integer number (3330936).

Almost surely, 2^21373429 is an apocalyptic number.

It is an amenable number.

21373429 is a deficient number, since it is larger than the sum of its proper divisors (5274059).

21373429 is a wasteful number, since it uses less digits than its factorization.

21373429 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 277595.

The product of its digits is 9072, while the sum is 31.

The square root of 21373429 is about 4623.1405992031. The cubic root of 21373429 is about 277.5181558881.

The spelling of 21373429 in words is "twenty-one million, three hundred seventy-three thousand, four hundred twenty-nine".