71621540 has 24 divisors (see below), whose sum is σ = 156945600. Its totient is φ = 27402848.

The previous prime is 71621509. The next prime is 71621549. The reversal of 71621540 is 4512617.

It is not an unprimeable number, because it can be changed into a prime (71621549) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 77390 + ... + 78309.

It is an arithmetic number, because the mean of its divisors is an integer number (6539400).

Almost surely, 2^71621540 is an apocalyptic number.

It is an amenable number.

71621540 is an abundant number, since it is smaller than the sum of its proper divisors (85324060).

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

71621540 is a wasteful number, since it uses less digits than its factorization.

71621540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 155731 (or 155729 counting only the distinct ones).

The product of its (nonzero) digits is 1680, while the sum is 26.

The square root of 71621540 is about 8462.9510219545. The cubic root of 71621540 is about 415.2865684139.

The spelling of 71621540 in words is "seventy-one million, six hundred twenty-one thousand, five hundred forty".