21662124377 has 8 divisors (see below), whose sum is σ = 22790212872. Its totient is φ = 20562595200.

The previous prime is 21662124359. The next prime is 21662124389. The reversal of 21662124377 is 77342126612.

It can be written as a sum of positive squares in 4 ways, for example, as 5252770576 + 16409353801 = 72476^2 + 128099^2 .

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 21662124377 - 2²⁰ = 21661075801 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (41).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21662124307) 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, 7138274 + ... + 7141307.

It is an arithmetic number, because the mean of its divisors is an integer number (2848776609).

Almost surely, 2^21662124377 is an apocalyptic number.

It is an amenable number.

21662124377 is a deficient number, since it is larger than the sum of its proper divisors (1128088495).

21662124377 is a wasteful number, since it uses less digits than its factorization.

21662124377 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14279659.

The product of its digits is 169344, while the sum is 41.

The spelling of 21662124377 in words is "twenty-one billion, six hundred sixty-two million, one hundred twenty-four thousand, three hundred seventy-seven".