15920551 has 8 divisors (see below), whose sum is σ = 16892064. Its totient is φ = 14952960.

The previous prime is 15920539. The next prime is 15920557. The reversal of 15920551 is 15502951.

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

It is a cyclic number.

It is not a de Polignac number, because 15920551 - 2⁵ = 15920519 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 (15920557) 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, 14446 + ... + 15508.

It is an arithmetic number, because the mean of its divisors is an integer number (2111508).

Almost surely, 2^15920551 is an apocalyptic number.

15920551 is a deficient number, since it is larger than the sum of its proper divisors (971513).

15920551 is a wasteful number, since it uses less digits than its factorization.

15920551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1961.

The product of its (nonzero) digits is 2250, while the sum is 28.

The square root of 15920551 is about 3990.0565158905. The cubic root of 15920551 is about 251.5664366062.

It can be divided in two parts, 15920 and 551, that added together give a triangular number (16471 = T₁₈₁).

The spelling of 15920551 in words is "fifteen million, nine hundred twenty thousand, five hundred fifty-one".