161261651015 has 4 divisors (see below), whose sum is σ = 193513981224. Its totient is φ = 129009320808.

The previous prime is 161261651011. The next prime is 161261651021. The reversal of 161261651015 is 510156162161.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 161261651015 - 2² = 161261651011 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161261651011) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16126165097 + ... + 16126165106.

It is an arithmetic number, because the mean of its divisors is an integer number (48378495306).

Almost surely, 2^161261651015 is an apocalyptic number.

161261651015 is a deficient number, since it is larger than the sum of its proper divisors (32252330209).

161261651015 is an equidigital number, since it uses as much as digits as its factorization.

161261651015 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32252330208.

The product of its (nonzero) digits is 10800, while the sum is 35.

The spelling of 161261651015 in words is "one hundred sixty-one billion, two hundred sixty-one million, six hundred fifty-one thousand, fifteen".