29185963921 has 27 divisors (see below), whose sum is σ = 31173918321. Its totient is φ = 27323306304.

The previous prime is 29185963913. The next prime is 29185963927. The reversal of 29185963921 is 12936958192.

The square root of 29185963921 is 170839.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 366148225 + 28819815696 = 19135^2 + 169764^2 .

It is not a de Polignac number, because 29185963921 - 2³ = 29185963913 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (29185963927) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 213036165 + ... + 213036301.

Almost surely, 2^29185963921 is an apocalyptic number.

29185963921 is the 170839-th square number.

29185963921 is the 85420-th centered octagonal number.

It is an amenable number.

29185963921 is a deficient number, since it is larger than the sum of its proper divisors (1987954400).

29185963921 is an frugal number, since it uses more digits than its factorization.

29185963921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 418 (or 209 counting only the distinct ones).

The product of its digits is 2099520, while the sum is 55.

The spelling of 29185963921 in words is "twenty-nine billion, one hundred eighty-five million, nine hundred sixty-three thousand, nine hundred twenty-one".