1651515157 has 4 divisors (see below), whose sum is σ = 1652074380. Its totient is φ = 1650955936.

The previous prime is 1651515149. The next prime is 1651515163. The reversal of 1651515157 is 7515151561.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 7515151561 = 337 ⋅22300153.

It can be written as a sum of positive squares in 2 ways, for example, as 482285521 + 1169229636 = 21961^2 + 34194^2 .

It is a cyclic number.

It is not a de Polignac number, because 1651515157 - 2³ = 1651515149 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 (1651515557) 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, 275158 + ... + 281095.

It is an arithmetic number, because the mean of its divisors is an integer number (413018595).

Almost surely, 2^1651515157 is an apocalyptic number.

It is an amenable number.

1651515157 is a deficient number, since it is larger than the sum of its proper divisors (559223).

1651515157 is an equidigital number, since it uses as much as digits as its factorization.

1651515157 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 559222.

The product of its digits is 26250, while the sum is 37.

The square root of 1651515157 is about 40638.8380370305. The cubic root of 1651515157 is about 1182.0273386256.

The spelling of 1651515157 in words is "one billion, six hundred fifty-one million, five hundred fifteen thousand, one hundred fifty-seven".