21512675390 has 16 divisors (see below), whose sum is σ = 38725194960. Its totient is φ = 8604541440.

The previous prime is 21512675363. The next prime is 21512675419. The reversal of 21512675390 is 9357621512.

It is a congruent number.

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, 133505 + ... + 246675.

It is an arithmetic number, because the mean of its divisors is an integer number (2420324685).

Almost surely, 2^21512675390 is an apocalyptic number.

21512675390 is a deficient number, since it is larger than the sum of its proper divisors (17212519570).

21512675390 is a wasteful number, since it uses less digits than its factorization.

21512675390 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 132187.

The product of its (nonzero) digits is 113400, while the sum is 41.

The spelling of 21512675390 in words is "twenty-one billion, five hundred twelve million, six hundred seventy-five thousand, three hundred ninety".