21423247377 has 8 divisors (see below), whose sum is σ = 32644948416. Its totient is φ = 12241855632.

The previous prime is 21423247337. The next prime is 21423247411. The reversal of 21423247377 is 77374232412.

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

It is not a de Polignac number, because 21423247377 - 2²⁶ = 21356138513 is a prime.

It is a super-2 number, since 2×21423247377² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21423247337) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 510077298 + ... + 510077339.

It is an arithmetic number, because the mean of its divisors is an integer number (4080618552).

Almost surely, 2^21423247377 is an apocalyptic number.

It is an amenable number.

21423247377 is a deficient number, since it is larger than the sum of its proper divisors (11221701039).

21423247377 is a wasteful number, since it uses less digits than its factorization.

21423247377 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1020154647.

The product of its digits is 395136, while the sum is 42.

Adding to 21423247377 its reverse (77374232412), we get a palindrome (98797479789).

It can be divided in two parts, 2142324 and 7377, that added together give a triangular number (2149701 = T₂₀₇₃).

The spelling of 21423247377 in words is "twenty-one billion, four hundred twenty-three million, two hundred forty-seven thousand, three hundred seventy-seven".