29145823821 has 6 divisors (see below), whose sum is σ = 42099523310. Its totient is φ = 19430549208.

The previous prime is 29145823801. The next prime is 29145823823. The reversal of 29145823821 is 12832854192.

29145823821 is a `hidden beast` number, since 2 + 9 + 14 + 582 + 38 + 21 = 666.

It can be written as a sum of positive squares in only one way, i.e., 26859932100 + 2285891721 = 163890^2 + 47811^2 .

It is not a de Polignac number, because 29145823821 - 2¹⁸ = 29145561677 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (29145823823) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1619212426 + ... + 1619212443.

Almost surely, 2^29145823821 is an apocalyptic number.

It is an amenable number.

29145823821 is a deficient number, since it is larger than the sum of its proper divisors (12953699489).

29145823821 is a wasteful number, since it uses less digits than its factorization.

29145823821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3238424875 (or 3238424872 counting only the distinct ones).

The product of its digits is 276480, while the sum is 45.

The spelling of 29145823821 in words is "twenty-nine billion, one hundred forty-five million, eight hundred twenty-three thousand, eight hundred twenty-one".