21940397351 has 8 divisors (see below), whose sum is σ = 22264834464. Its totient is φ = 21616388640.

The previous prime is 21940397329. The next prime is 21940397377. The reversal of 21940397351 is 15379304912.

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 21940397351 - 2⁶ = 21940397287 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21940397321) 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, 3176 + ... + 209501.

It is an arithmetic number, because the mean of its divisors is an integer number (2783104308).

Almost surely, 2^21940397351 is an apocalyptic number.

21940397351 is a deficient number, since it is larger than the sum of its proper divisors (324437113).

21940397351 is a wasteful number, since it uses less digits than its factorization.

21940397351 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 214201.

The product of its (nonzero) digits is 204120, while the sum is 44.

The spelling of 21940397351 in words is "twenty-one billion, nine hundred forty million, three hundred ninety-seven thousand, three hundred fifty-one".