21910129074 has 128 divisors (see below), whose sum is σ = 52406092800. Its totient is φ = 6760765440.

The previous prime is 21910129069. The next prime is 21910129079. The reversal of 21910129074 is 47092101912.

It is an interprime number because it is at equal distance from previous prime (21910129069) and next prime (21910129079).

It is not an unprimeable number, because it can be changed into a prime (21910129079) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 28790854 + ... + 28791614.

It is an arithmetic number, because the mean of its divisors is an integer number (409422600).

Almost surely, 2^21910129074 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21910129074, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26203046400).

21910129074 is an abundant number, since it is smaller than the sum of its proper divisors (30495963726).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21910129074 is a wasteful number, since it uses less digits than its factorization.

21910129074 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1265 (or 1259 counting only the distinct ones).

The product of its (nonzero) digits is 9072, while the sum is 36.

The spelling of 21910129074 in words is "twenty-one billion, nine hundred ten million, one hundred twenty-nine thousand, seventy-four".