21436464870 has 48 divisors (see below), whose sum is σ = 55832551632. Its totient is φ = 5706365760.

The previous prime is 21436464869. The next prime is 21436464913. The reversal of 21436464870 is 7846463412.

21436464870 is a `hidden beast` number, since 214 + 364 + 6 + 4 + 8 + 70 = 666.

It is a super-2 number, since 2×21436464870² (a number of 21 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 157177 + ... + 259956.

It is an arithmetic number, because the mean of its divisors is an integer number (1163178159).

Almost surely, 2^21436464870 is an apocalyptic number.

21436464870 is an abundant number, since it is smaller than the sum of its proper divisors (34396086762).

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

21436464870 is a wasteful number, since it uses less digits than its factorization.

21436464870 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 417717 (or 417714 counting only the distinct ones).

The product of its (nonzero) digits is 774144, while the sum is 45.

The spelling of 21436464870 in words is "twenty-one billion, four hundred thirty-six million, four hundred sixty-four thousand, eight hundred seventy".