21836494747 has 16 divisors (see below), whose sum is σ = 23323243680. Its totient is φ = 20372986368.

The previous prime is 21836494727. The next prime is 21836494763. The reversal of 21836494747 is 74749463812.

It is a cyclic number.

It is not a de Polignac number, because 21836494747 - 2⁷ = 21836494619 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21836494727) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 915904 + ... + 939442.

It is an arithmetic number, because the mean of its divisors is an integer number (1457702730).

Almost surely, 2^21836494747 is an apocalyptic number.

21836494747 is a deficient number, since it is larger than the sum of its proper divisors (1486748933).

21836494747 is a wasteful number, since it uses less digits than its factorization.

21836494747 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24030.

The product of its digits is 8128512, while the sum is 55.

The spelling of 21836494747 in words is "twenty-one billion, eight hundred thirty-six million, four hundred ninety-four thousand, seven hundred forty-seven".