81421979754 has 16 divisors (see below), whose sum is σ = 162846888480. Its totient is φ = 27140171760.

The previous prime is 81421979729. The next prime is 81421979761. The reversal of 81421979754 is 45797912418.

It is a junction number, because it is equal to n+sod(n) for n = 81421979694 and 81421979703.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 434757 + ... + 593175.

It is an arithmetic number, because the mean of its divisors is an integer number (10177930530).

Almost surely, 2^81421979754 is an apocalyptic number.

81421979754 is an abundant number, since it is smaller than the sum of its proper divisors (81424908726).

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

81421979754 is a wasteful number, since it uses less digits than its factorization.

81421979754 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 244085.

The product of its digits is 5080320, while the sum is 57.

The spelling of 81421979754 in words is "eighty-one billion, four hundred twenty-one million, nine hundred seventy-nine thousand, seven hundred fifty-four".