61572021 has 16 divisors (see below), whose sum is σ = 95821824. Its totient is φ = 34434864.

The previous prime is 61572019. The next prime is 61572031. The reversal of 61572021 is 12027516.

It is not a de Polignac number, because 61572021 - 2¹ = 61572019 is a prime.

It is a super-2 number, since 2×61572021² = 7582227540048882, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 61571982 and 61572000.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61572031) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 30205 + ... + 32178.

It is an arithmetic number, because the mean of its divisors is an integer number (5988864).

Almost surely, 2^61572021 is an apocalyptic number.

It is an amenable number.

61572021 is a deficient number, since it is larger than the sum of its proper divisors (34249803).

61572021 is a wasteful number, since it uses less digits than its factorization.

61572021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 62440.

The product of its (nonzero) digits is 840, while the sum is 24.

The square root of 61572021 is about 7846.7841183507. The cubic root of 61572021 is about 394.8763614536.

Adding to 61572021 its reverse (12027516), we get a palindrome (73599537).

The spelling of 61572021 in words is "sixty-one million, five hundred seventy-two thousand, twenty-one".