21374351 has 2 divisors, whose sum is σ = 21374352. Its totient is φ = 21374350.

The previous prime is 21374333. The next prime is 21374357. The reversal of 21374351 is 15347312.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21374351 - 2¹⁰ = 21373327 is a prime.

It is a Sophie Germain prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21374351.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21374357) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10687175 + 10687176.

It is an arithmetic number, because the mean of its divisors is an integer number (10687176).

Almost surely, 2^21374351 is an apocalyptic number.

21374351 is a deficient number, since it is larger than the sum of its proper divisors (1).

21374351 is an equidigital number, since it uses as much as digits as its factorization.

21374351 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2520, while the sum is 26.

The square root of 21374351 is about 4623.2403138924. The cubic root of 21374351 is about 277.5221463266.

The spelling of 21374351 in words is "twenty-one million, three hundred seventy-four thousand, three hundred fifty-one".