16121561215 has 8 divisors (see below), whose sum is σ = 19346564448. Its totient is φ = 12896788320.

The previous prime is 16121561207. The next prime is 16121561257. The reversal of 16121561215 is 51216512161.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 16121561215 - 2³ = 16121561207 is a prime.

It is a Duffinian number.

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, 206545 + ... + 273685.

It is an arithmetic number, because the mean of its divisors is an integer number (2418320556).

Almost surely, 2^16121561215 is an apocalyptic number.

16121561215 is a deficient number, since it is larger than the sum of its proper divisors (3225003233).

16121561215 is an equidigital number, since it uses as much as digits as its factorization.

16121561215 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 115169.

The product of its digits is 3600, while the sum is 31.

The spelling of 16121561215 in words is "sixteen billion, one hundred twenty-one million, five hundred sixty-one thousand, two hundred fifteen".