161421399810 has 48 divisors (see below), whose sum is σ = 457849791360. Its totient is φ = 39132460320.

The previous prime is 161421399773. The next prime is 161421399823. The reversal of 161421399810 is 18993124161.

161421399810 is a `hidden beast` number, since 1 + 61 + 421 + 3 + 99 + 81 + 0 = 666.

It is a super-2 number, since 2×161421399810² (a number of 23 digits) contains 22 as substring.

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

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, 81524970 + ... + 81526949.

It is an arithmetic number, because the mean of its divisors is an integer number (9538537320).

Almost surely, 2^161421399810 is an apocalyptic number.

161421399810 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

161421399810 is an abundant number, since it is smaller than the sum of its proper divisors (296428391550).

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

161421399810 is a wasteful number, since it uses less digits than its factorization.

161421399810 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 163051943 (or 163051940 counting only the distinct ones).

The product of its (nonzero) digits is 93312, while the sum is 45.

The spelling of 161421399810 in words is "one hundred sixty-one billion, four hundred twenty-one million, three hundred ninety-nine thousand, eight hundred ten".